Ever since Apple released Final Cut Pro X today, there's been a flood of tweets and blog posts offering instant analysis, most of them referring to missing features and capabilities, such as the inability to import previous FCP projects into FCPX. Some of the complaints are just plain wrong; for example, one person tweeted that FCPX can't use shared media, then tweeted a bit later that it can.
One thing that some commenters are getting right is that this is Final Cut Pro X Version 1, not Final Cut Pro Version 8. It's (apparently) an entirely new code base, with a dramatically different user interface, and different terminology for some of the same functions in previous versions. Version 1.0 of a new product always has bugs and missing features. It's a given with any software product, and FCPX is no different.
If you're already using Final Cut Pro 7 or Final Cut Studio, you should continue to use it for deadline-based and revenue-producing jobs while you get up the learning curve on FCPX. Even if FCPX was a completely incremental release, I'd still be suspicious of switching to it immediately. New releases always have bugs. However, if you're an existing Final Cut Pro user and you can afford the $300, I'd suggest that you buy it, in order to learn the software on your own schedule. This is the future of Final Cut Pro, and unless you want to eventually abandon the platform entirely, you'll need to understand and use it.
On the other hand, if you're a new user or you have questions or concerns, there's no risk in waiting. Those "instant" reviews are likely to be largely appended, corrected and superseded over the next few weeks. Let others dig into the software and give you their feedback.
When OSX Lion ships next month, the App Store will be integrated into the operating system, and updates will be much faster and easier than they are today. Only the parts of the code that need to be changed will be updated, not the entire application, so downloads and installation will be much faster. Over the next few weeks and months, Apple will release updates, and third parties will release utilities and drivers to correct or compensate for the more serious shortcomings in FCPX.
In short, don't panic. This isn't a race.