Windows 7: 64 bit computer shipped with 32 bit Office

Hi, I recently built a DELL 8300 XPS 64 bit computer on line and purchased it. I had Microsoft Office Business included. Yesterday I got the Office SP1 update via Windows Update, and the 32 bit version was downloaded. Upon checking, I see they installed the 32 bit version of Office rather than the 64 bit version. Why would they do that? Am I at a disadvantage? Thanks for any response.

The main reason is app compatibility, which is why 32-bit Office 2010 is recommended even on 64-bit Windows. There are very few if any 64-bit add-ins for Office. For a more thorough discussion on the difference between 32-bit and 64-bit Office, please take a look at these docs:
per Office forums A and Q

OK so that's it eh? I had checked a little further and found a page with a choice of downloading 32x or 64x. The 32x download is 350 something MB, and the 64x is 500MB. Thanks for the info!

Glad to be of help
I have office and use 32, myself. Never really had concern about the reason

You want to use office 32 bit. That's all that I would use for compatibility purposes, and it's what Microsoft actually suggests that people run.

Agreed.
64bit Office is buggy with its compatibility with anything.

Seems like there is a lot of confirmation on the reason, thats a good thing.

The 64 bit version of Excel doesn't suffer from the limited number of cells available in the 32 bit version.

I've needed that feature exactly once, so far.