If you’re chomping at the bit to try iWork ’09, Apple has posted a 30 Day trial of the application that you can upgrade to the full version at any time – just like with previous incarnations of the software.
So don’t worry about ordering it online and having it shipped, or stopping by an Apple store – you can get it right now.
I downloaded it last night, and spent a few minutes with it, but not enough time yet to have an opinion on if it’s worth upgrading or not. Hopefully after Macworld I can spend some time with the software and get a good look at it. Right now, it’s hard to notice much change, just glancing at it.
You can get the download here and give it a try for yourself right now.