Settle down, guys.
Okay, you're right, it'll probably work but not for sure. Then again, I've heard reports of Crucial not working either. Either way, if it doesn't work, you can send it back and get a new one. It's not a compatibility issue since technically the PowerBook uses that exact type of RAM (even if it doesn't adhere perfectly to the Apple spec). So if it doesn't work, it means it's defective. Maybe a PC would work with it, since PCs tend to be less picky, but it's not incompatible with Macs.
I'm not sure if "a bit more likely to work as soon as I get it" is worth spending $136-$216 extra for. Crucial is great, I agree, but they charge SO much for 1 GB SODIMMs. $150 at Outpost vs. $286 at Crucial. In fact, Crucial even manages to ream Mac users more by making the RAM pulled up by their system configurator cost $80 extra for no reason.
CT12864X335 1 GB, PC2700, CL 2.5, DDR333, 2.5V, 128Mx64, $286
CT434204 1 GB, PC2700, CL 2.5, DDR333, 2.5V, 128Mx64, found using system configurator, $366