Both 32 and 64bit are available on the disk, I don't see a problem switching between the two if that's your thing

I doubt that they will give you seperate keys for 64 bit and 32 bit since they are on the same disc. Why would you want to run 32 bit anyway?

Because you don't remove one carabiner to hook onto the next rope without ensuring that your backup is secured.  Simple as that.

Frm what I gather, even though you may get both flavors on your disc (both for retail and OEM), you won't be able to switch between them.

I'm running Windows 7 RTM already here's how it works.

Windows 7 will only allow you to install the version you bought - if you bought business 32bit you get the 32 bit version of  not the 64 bit version. so no you can't switch between them. In that sense it works just like Vista you enter your key and thats what you can install - if you choose not to enter your key and install the wrong verion it -wont- work.

Also the versions do not share the same disk the disk either has x86 softeware or x64 software - atleast this is how it works for the RTM version.

Same for the OEM version.

Hardware manufactures don't care they'll sell you what you want. What you need to worry about are softeware people - If you dont run ANY 16bit programs then you dont need the 32bit version bypass it completely. The 64bit version is fine now and the RTM doesnt even go public until the 22nd of October - drivers are there, it feels like a MS OS that has already seen SP1 - so unless you've got really really old software on your computer that you cant run in a VM just buy the 64 bit edition you wont need the 32 bit version.

Um, if it's anything like Vista, I had so many people tell me no you can't swap between 64 bit and 32 bit, you get what you buy.  They were absolutely sure.  They were all absolutely wrong.

I've swapped between them (yes, with activations) fine, so have friends of mine since then...  

You would have to create 2 partitions on your harddrive, install 32 bit on one and 64 bit on the other.. But since you used the product key (lets say) for the 32 bit edition activation, you would need another key to activate the 64 bit version.. When you boot up your computer a boot manager will display asking which version (partition) to load.. The biggest problem with 64bit is you are limited to newer software..

Although there is software that will allow Windows 7 to run a virtual XP enviroment.. So you could run XP software

From the Microsoft product page for the full version Windows 7 Home Premium:

This product includes both 32-bit and 64-bit versions.

http://store.microsoft.com/microsoft/Windows-7-Home-Premium/product/7ADA0BF6

seems you get both on one disc.  They did that with Vista Ultimate but only for retail versions, OEM were limited to what you bought. 

Thank you Rob.  That's about what I needed to know.

I use a boot loader and i can choose between OpenSolaris ( sun unix ), Kubuntu ( linux ), XP pro x64 ( retail version ), Vista 32 and Vista 64 ( OEM version 32 and 64 have the same key )...

For the boot loader, i use a linux version since the windows version don't see my ext3 partition...

Any idea if you can upgrade vista 32bit to windows 7 64bit? Because the morons at HP put a 32 bit os on my laptop with 4gb. I've been running the windows 7 beta (64bit) since i bought it.

@ Wieke:

i'd always say your best off with a clean install over an upgrade. i saw an article released by microsoft where an upgrade to 20+ hours to complete. this was with a load of user data and applications and not the fastest of hardware but still. also an upgrade will always leave cruft from vista in your os folders.

if you're going to be starting a new OS might as well start it as best as possible.

i've a question regarding 32 and 64 bit and activations.

Thoumsin, you say that you can dual boot both OSes without activation issue. any ideas if i'd be able to install 64 to my main desktop and use 32 on my netbook?

purely hypothetical actually as i've a 901 so only 4gb OS drive. still it'd be usefull to know if/when i upgrade.