Win 7 coupon w/ Vista... Why wait & buy retail?

I've been doing a bit of research, but wanted to ask you fine people before I make a decision.

I am planning on purchasing Windows 7 Prof 64 bit, but I have a question about the free upgrade coupon that Newegg is offering w/ Vista. Why would I wait until Oct 22nd to pay $300 when I can buy Vista business 64 w/ the Win 7 upgrade coupon right now for $150? I've read a few forums and poked around the web, but I can't find a solid answer. Is there something I'm just completely missing? I am currently running Vista home premium 32.

I think you are "completely missing something". The $150 is for an OEM copy (you provide your own tech support). The $300 is for a Retail copy (MS provides tech support). Because you already have Vista, you qualify for the Upgrade version, which is $200. Not sure if that includes support or not, but it will transfer over your programs, settings, and files from your Vista install.

Yes, you can buy the upgrade! The upgrade version includes both the 32-bit and 64-bit versions of Win7. Now, if you're going from 32-bit to 64-bit, you can't have it transfer files, settings, programs, etc. You'll have to back up that stuff yourself and restore to the new, 64-bit OS. But the upgrade version can also perform a "clean install", i.e., it completely overwrites the previous OS and then installs the new one. The only requirement is that you have an activated previous version of Windows installed for it to overwrite. You do. In a nutshell, then, you can use the upgrade version to go from 32-bit Vista to 64-bit Win7. However, your files, settings, and programs will not be transferred.

i'm running windows 7 ultimate retail and it runs smooth!go for it j

Yes, to really reinstall your OS you would have to reinstall Vista first and then go to Win7. An easy way around that, though, is to simply take an image of your HDD just after you install Win7, before you have installed any other programs. Then you can re-image the drive each time instead of reinstalling: same net effect, but faster and easier. If you really don't want to use imaging, then go with Win7 OEM.
About x86/x64 with OEM, you can purchase one or the other. You have the "right" to whichever version you purchase. For the vast majority of system builders today, that should be x64.