Fedora is an interesting distribution compared to Ubuntu. I like to think of it as more of a developer platform than anything else. It tends to get the latest and greatest new toys first, thanks largely to the amount of investment Redhat pours into it.
The flip-side to that of course is that sometimes new packages really aren't ready for mass-adoption and this can lead to all sorts of head-aches. Fedora was the first distro to get things like pulseaudio and ati kernel-mode-setting. Both of those things made the first distro they appeared in nearly unusable for me, but now we're starting to see those features everywhere.
The other major difference is the core package set that's available. Ubuntu tends to include everything in their default repositories, whereas Fedora excludes proprietary software, including patented codecs (ie, mp3 support). This is easily worked around by adding extra package sources (
http://rpmfusion.org/ being the most important), but the average newb wouldn't know that, they'd only know that their music and movies don't work.
So in short, if you want to see what everyone else will be using in 12 months, go with Fedora, but be prepared for some wonkiness that goes with living on the bleeding edge.
