M3 is definitely a good choice but It all depends on what you can see yourself doing in the future. When kind of camera can you see yourself using in 2-3 years? Is it a DSLR, mirror-less or even a camcorder. If it's a DSLR it's best to get a DSLR now. You will be able to transfer all your lenses and you will be more familiar with how to use it.
If it's anything else then your current purchase shouldn't have to much of an impact on your future setup.
What do you think about my t3i/t4i suggestion? it doesn't have a flip out screen but other than that it can be a good choice in your situation.
Haha, well truth be told - it might just be a setup for 1 year (long story short, friends company is setting up a video space akin to a YouTube space with top of the line equipment in 2016.
ANd I do like the t3i/t4i suggestion - I think if I go that route I'd buy used, and am looking online now.

Haha, oh man camera shopping is fun!