I think its Vista Premium to 7 Premium...
I've ordered it, and fortunately where I live its free of charge, I'd heard stories about a lot of the companies offering the free upgrade and then charging £18.99 to ship it... Which is a joke to be honest...

Anyway it came within 16 hours of me ordering, had a play with it and its good..
Perfect for what I need it for, plus if I want to play the odd game I can... But I think I'll leave that to my desktop or the Xbox360...

A steal at £360, it really is... Built very well, not packed full of crapware like some of the others... (Dell)... All I really had to uninstall was Norton, which I replaced with the free version of AVG...

Carry case for a tenner is fantastic, as is the Sandisk 8gb USB Key...

Chuffed to bits with this purchase...

Thank you all for you help!