Windows 7: Question on 7 basic

Question on 7 basic, you can upgrade from as low as XP SP3 - the licensing is so convoluted, and it seems like they are more concerned with OEM (why buy a full priced OS off the shelf if you could buy an OEM and do whatever you wanted with it?) than the status of an upgrade/previous OS.
Couldn't find 7 on the Microsoft store site, and their marketing it "as a windows 7 with the wiz-bang". I very much doubt that to be true.

I for one would be very pissed off if I upgraded and had second thoughts, didn't like the product, had driver issues, problems with applications, etc - and would expect an option where if Microsoft really wanted me to buy into the new OS, be able to go through an evaluation phase (not trial) while retaining my old software and not compromising my old system setup.

If there were any specific concern for me it would be all the integrated active content from the App Store. Is Microsoft moderating apps? I don't like the way apps get lost in the back ground (is there an app 'task' manager and should we be worried about security vulnerabilities?