The only other problems you might come across is that x64 requires digitally signed drivers. This might be a problem if you have some programs by small developers that can't afford the certificate from Microsoft.
Does Linux have to be brought up in every single computer thread?
I run Vista Business x64 and I haven't found any problems related to it being 64-bit. 64-bit installations are starting to become popular enough that developers are taking it into consideration for drivers and such. I'm not really sure about the OEM discs, but the retail DVDs can install 32- or 64-bit versions.
It's actually a good thing, considering the fact that many Windows issues arise from poorly implemented third-party software and drivers. Requiring signed drivers is one way that Microsoft can ensure that Vista x64 is as reliable as possible, which will probably be a priority to the experienced user who is probably aware of the pitfalls that come with a 64-bit environment.
I've been running Vista Ultimate x64 just short of a year now and have been very pleased with it. I have run into a few surprising incompatibilities, however, and I would highly recommend dual-booting your system just in case. I'm triple booting Vista x64 with a 32-bit edition of XP (and Ubuntu), so any incompatibilities can be solved in the time it takes to reboot.