Sooo..... any further informations about those? It appears that those were given out even BEFORE the Alpha Kits? XPK stands for Xbox Prototype Kit. A Keyword I'd throw in is: [FONT=Bookman Old Style, serif]Xbox Independent Developer Program dating back to (at least) 2000.[/FONT]
Sounds just like a fancy name for an Alpha one. There are Alpha ones that can be dated all the way back to June of 2000.
In fact, that could might be, although I am wondering why M$ itself would use that fancy name, while they usually just called them "[FONT=Bookman Old Style, serif]PC-based XDK system" or just "XDK"[/FONT]
