Thief 4 was a no-show at E3, marking another trade show without mention of the long-silent game. According to several resumes from staff members, the project seems to have lost some of its talent and could be facing trouble.
Kotaku, with the aid of Superannuation, reports on a string of potential bad news for the game. According to recent resumes, audio director Paul Weir and level designer Adam Alim have left the studio; Alim replaced Pierre-Olivier Clement, who moved to another project at Eidos Montreal last year. Other recent departures have included two senior concept artists, a senior technical level designer, a senior animator, and a senior level designer.
On top of that, a trailer was purportedly set to be released in December of 2011, and some of the footage appears in a demo reel (seen below). The trailer appears to be done for all intents and purposes, but Square Enix seems to be holding it back.
On the other hand, one level designer says he designed "the last level of the game." That at least implies that the game has enough of its roots in place to establish finality, even if game design doesn't always (or even usually) follow in sequential order.