In a rare move, Chair Entertainment was able to send out download codes for "Shadow Complex" more than a week before the game releases to the world on XBLA. So, of course, I've been playing a lot of it. My review is embargoed until next week, but I thought you guys might be interested to learn just how quickly the game can be finished.
Let me preface by saying that your first time through the title will probably take around 6-8 hours. The above "speed run" times were from second and third play-throughs of the game, when players are already familiar with the map, have a boosted up character level (your level carries over to subsequent play-throughs) and have other "advantages" which I won't delve into since they may be considered spoilery.
In case you're wondering, I'm number 2 on that list, with a time of 1:10:20. That play-through (my third) was on the easiest difficulty setting, but didn't involve any sequence-breaking techniques (i.e. getting certain items way earlier than the game intended). I didn't go for any side items (ending the game with just 11% of the items collected) and I skipped all the cutscenes. Oh, and number 1 on the list is Joystiq's own Xav de Matos, who bested me by about 6 minutes. The jerk.
Once the game releases, I'm sure the speed run leaderboards will be overtaken by insane Europeans who have figured out how to complete the game in under 3 minutes while blind folded and drunk. Until then I'm going to bask in my #2 slot.