I'm using the Panasonic Lumix GF2 with the Panasonic Lumix 20mm F1.7. The system isn't exactly DSLR but it's referred to as mirrorless cameras or specifically Micro Four Thirds since there are other mirrorless cameras that have sensors that are bigger and smaller than the micro four thirds size.
It's a relatively new system that's been out since I think the end of 2008 and gaining more popularity due to its compact size but increasing image/video quality. The 2 companies that have Micro Four Thirds systems are Panasonic and Olympus.
If you own any brand Micro Four Thirds lenses, they work on all Micro Four Thirds bodies whether its Olympus or Panasonic. Olympus and Panasonic have their own lenses and are creating more higher end but also more expensive lenses. 3rd party companies are also making Micro Four Thirds lenses which gives the m4/3 users a ton of lens options.
Other companies are trying to compete with the M4/3 systems, mainly Canon and Nikon. They have their own versions of high quality compact cameras but their models are in the beginning stages and aren't as great compared to the M4/3 systems. I can get into why some other time lol!
One of the main plus sides of going to the M4/3 route is that it's a great hybrid camera, meaning great for shooting video and stills at the same time and the while being super compact. But what matters most is what you want to use it for. Me for example, I like how its compact and I take it with me daily. If I had a bulkier DSLR, I'd only carry it on me when I know I'm going to use it. Since I like taking photos or vids on the fly or candidly, the GF2 is great because I'm already carrying it and is super low profile.
M4/3 are creating more professional camera bodies. The workhorse as of late is the Panasonic GH2. It's a great model for film making and stills. For film making, it has the 24 fps that cinema cameras use. Also it handles low light very well and has a LCD screen that can flip out. There's much more to it but you can google it if you're interested. Right now it is becoming more affordable because it's been out for about 2 years or so and the GH3 just came out within this month. The camera body is not as low profile but the body is much smaller than traditional Micro 4/3 systems.
One of the things that I was mentioning about the downfalls of the GF2 is it's manual controls in video mode, it doesn't have much. I can adjust the format(resolution and fps) and shutter speed but not the aperture and ISO settings, those two are automatic. Shooting video in low light isn't so much an option(which is why the GH2 is a very tempting camera for me in the near future but we'll see!).
The GF2 has been out for a while and is still a great camera but the newer versions that are out there are better. What I like about the GF2 though is that it has a hot shoe mount so I can place my shock mount on top when I place my audio recorder on top for external audio. Also if I don't use my Zoom H1, the in camera mic records in stereo(GF3 is in mono but I think the GF5 brought stereo back.) The hot shoe mount can also be used with an external viewfinder and also an external flash I think. The GF3 and GF5 no longer have the hot shoe mounts. The only ones are the GF1, GF2, the G and GH series. Most users don't use it anyway but it's always good to have that option though.
Another knock on the GF2 in regards to film making is that the LCD screen resolution is something like 460K dots or something along those lines. It makes it difficult to see if I'm really in focus but in manual mode, the LCD will zoom in then you can manually focus then zoom back out. I just started doing that for our films and it works well but I'd also like to have a higher rez LCD anyway and the GF5's LCD is at 920K dot display.
The cool thing about the Olympus M4/3 cameras is that many if not all, not sure I have to look it up...have image stabilization built in the body and Panasonic doesn't. Not sure if the GH2 or GH3 have it built in, I have to look that up later. Also the older and lower end Panasonic lenses don't have image stabilization. This doesn't mean much to me from a still pictures point of view but means a lot from a film making perspective. It's kind of the reason why my camera movement when shooting the short film was mainly fixed and little panning with a tripod and the stuff I did with the dolly. I did some hand held during my shoot because the shots were static and it's easier to get close up without the tripod.
Another thing about the GF2 is the autofocus. It works well but it does focus hunt a lot and that's not great for video. I had to do some pull/rack focusing in manual mode during my shoot but had a difficult time figuring out if I was in focus since my screen rez isn't high and the sun reflected off of the LCD screen. An optical viewfinder would work better in those type of situations or that monitor that Carlos let Christian use for Megan's shoot!
If you are going to go with the M4/3 route then I'd pic the workhorse lens of the M4/3 world is the Lumix 20mm F1.7 which costs about 350 or so which is pretty pricey but it's the reason why I have some pleasing video. With camera bodies, it will depend. If you don't need a hot shoe mount but want something compact then I'd say the new GF5 for stills and video(sans low light shooting). I'd also recommend the GH2(can be hacked to give it a much higher video bitrate). It's an older model now since the GH3 came out but many indie shooters still use it and will still be relevant for years to come. If money is not an issue then I'd go with the GH3. It can shoot stills and video in almost all situations. There are many videos on Vimeo that compare it to other cinema cameras and the Canon Mark III.
You can also go the Olympus route but I haven't delved into their camera bodies much since my eye are very much set on one of the GH models. The EM-5 and the PEN models are great.
There are deals on the M4/3 all the time so there really isn't a need to rush but most deals come with the kit lens. If it's a good deal, I'd say get it then sell the kit lens and use the extra funds to get the 20mm F1.7. The only thing is that you'll have only that focal length until you buy another lens or decide to keep the zoom kit lens if it's to your liking. I'm not sure what my 2nd lens is going to be but may look for a higher end zoom lens or a high end wide angle lens but we'll see.
I hope I was informative. Just ask me whatever questions you have and I'll let you know what I think. The only thing that surprised me is that not many, even our professor wasn't too familiar with the M4/3 systems. Elson was but he hasn't had his hands on one.
Before I forget, Sony has their line of mirrorless but not M4/3. Their sensor size is pretty much equivalent to the cropped sensor DSLR's like the Canon 7D, T4i, etc. They have great low light capabilities and super compact. I noticed that the focus isn't as tack sharp and their interface is a bit clunky in my opinion but you can research those out as well. They are still awesome cameras for stills and video.