By Centrino I suppose you refer to the Pentium M processor. Well, right now P-Ms operate at 400MHz FSB but in Q2 2004 it is expected that Intel will introduced the new 90nm P-Ms, utilising a 533MHz FSB.
I also suppose that the reason you so eagerly want P-M with a 800MHz FSB is because you know that Pentium 4s have that bus and deffinetely 800 looks more impressive than 400 or even 533. Don't be fooled by raw numbers though. The P-M is still a great processor. A 1.6GHz P-M for example with 400MHz FSB can kick the ass of a 2.4GHz Pentium 4 using a 800MHz FSB. FSB is exactly right clock speed. On its own it doesn't determine performance, when talking about two absolutely different chip architectures. It can only be considered, like clockspeed, as a way of comparison, only when comparing chips within the same family.