I prefer the current voting system; but then again there are always downfalls to the current way. There are many well done movies that are voted quite lowly and are underrated. Although I try to vote using X and 0-5, the one to four votes make it quite difficult to keep in a good movie.
The thumbs up/thumbs down idea is good. It's simplistic, and there are many people here who prefer the simplistic stuff instead of more complicated and technical stuff since they hate to think for once, especially when it's not about themselves *cough*
The only concern I have is about the experience votes. I guess I'm not sure about it, but it'll be like the 5.56 votes (example only) would then turn into 5.56 thumbs up or something along the lines.