It's the same thing, but, there is no tech support for the OEM version(I don't think) and you have to buy it with other computer parts like a mobo, processor and some other stuff that's why it's the "system builders" version.
Another big point is that you can only use an OEM copy on one computer. If you try to "activate" it on a second system, or a rebuilt system with different parts, I am pretty sure you'd meet some resistance. I believe it's the same deal as activating XP, when you changed too many parts, you'd have to call microsoft (at least that's what the people without a corporate edition told me).
OEM is valid for only one computer.
The retail can be transferred to another computer.
I would buy the OEM and wait for Windows 7.
If you buy the retail, you may not want to carry it over to the next computer. Sounds like Windows 7 is going to be better.
I digitally downloaded Vista, for 10 bucks ontop of the 90 i paid for it, they will send me a cd with both 32 bit and 64 bit on it. Plus i didnt have to wait for the mailman. Also oem lets you put windows on 3 personal computers at home, that is what is in the fine print of the liscence agreement.
I've used XP Pro, Vista Home Premium and Vista Ultimate. All OEM versions. On each one, I've transferred them from one build to another with no problems from Microsoft. The XP has been on 5 different computers and activation over the internet has never failed yet. I've gotten a message about having to reactivate becasue of parts I've switched out, but only once have I ever had to call Microsoft and they just asked if I had uninstalled it from the previous machine. I told them the parts from the old one were on Ebay and they gave me a new activation number without problem. Both versions of Vista I've transferred to new builds and reactivated without any problem.
Microsoft is having enough trouble selling Vista without pissing people off by being picky about moving it from one system to another.
If you ever get a message saying you have to call, just be honest and tell them what you're doing. If you're just rebuilding with some new componenets or if you've disassembled the old system, they won't give you any problems.
If you ever need support, you can find out anything you need by searching on the internet or searching the Microsoft knowledge base.
^too right comrade.
I wish I just called Microsoft about my XP OEM to reactivate it (think I only had the same mobo left in the system)... I actually bought a license, but I borrowed my dad's corporate edition instead of jumping through MS hoops.
Anyway if you read the new license agreement on Vista it mentions unlimited transfers, you just have to uninstall it each time first (I think Apple only gives you 3, as did the old Vista agreement). Not sure it applies to OEM, but like it has been mentioned, you will probably get an upgrade version of 7 when it comes out (from what Ive heard and read it'll be good, especially cause MIcrosoft hasn't really promised anything).