Its not a graphical upgrade its a limitation. XI on the xbox was terrible, no support for it really, and disc error only cureable by uninstalling/reinstalling with another xbox harddrive. That system sucks, 3 discs for FFXIII lol, guess they lost out with "hd dvd". XI was suffering from limitations due to ps2, and it wasn't graphical since PC has best graphics, and xbox is comparable to pc, it was due to space. Not everyone is going to buy the special addition star wars xbox, or xbox memory upgrades just to play XIV.

On another note Xbox also wants to get a cut of all subscriptions for mmos which come to their system, that alone has killed some mmos going to xbox, the XBL silver thing for xi probably irks Microsoft to no end that they agreed to that.

Sony and SOE/PSN are way more mmo friendly, but mmos owned by SOE suck, (NGE really!?!?)