Pre-orders are supposedly in the 1 million territory currently. That's a pretty fair indicator that the game should be a commercial hit.
Anyone who's played the demo should have their own opinion whether the game should be good or bad. There's no better "review" than a good demo after all.
http://xboxoz360gamer.com/2008/08/03/too-human-rumour-report-shows-1-million-preorders/
“According to sales reports from Gamestop, EB Games, and Microsoft Co., there were an estimated 1.4 million preorders placed in the contiguous U.S. during the one-year period leading up to E3, 2008. After the release of the game’s demo a reported 370,000 additional games were preordered, in addition to 495,000 cancellations.
During the E3 conferences and in the week after, a mere 45,000 preorders were cancelled while 350,000 more were made. There were only a reported 8,000 cancellations during the year prior to the demo’s release.”







