FCP X has a lot of cool new features, some probably ahead of their time. But where it succeeds in innovation, it lacks in other areas, notably its neutering of basic workflow features that professional editors need to earn a living.
But for some, this doesn't really matter. In fact, in many ways, it's a godsend for web video guys. So I think it's really going to come down to whether the new version will work out in your situation or not. Personally, it doesn't work for me yet (and it has yet to be determined if it ever will). I would say that FCP X is an excellent upgrade if:
1. You don't need EDL/XML functionality (for sharing edit data with other software and 3rd parties).
2. You don't work extensively with tape.
3. You don't need numbered A/V tracks and OMF export support (important if you work with sound mixers on ProTools and similar DAWs).
4. You don't work with professional raw video codecs like REDCODE or ARRI RAW (for which no plugins exist yet for FCP X).
5. You don't need professional video I/O for broadcast monitors and the like.
6. You don't have important projects from an earlier version of FCP in progress (FCP X doesn't open older projects AT ALL).
There's probably other things I'm not thinking about right now, but at least 5 of those things apply to me, so FCP X isn't ready for primetime in my situation. I can only hope in the future that it will be.