Although it had already been rumored for a while, today everything pretty much became solidified for the reality of a Hitman HD collection. The game cropped up on Amazon and even had its Achievement listings sent out to Xbox360Achievements (PS3 Trophies were discovered earlier). This is probably the best time as any for this set to come out as Hitman: Absolution recently launched.
Hitman Trilogy HD will include the following three games: Hitman: Contracts, Hitman 2: Silent Assassin, and Hitman: Blood Money. This collection only misses Hitman: Codename 47, which was the first game in the series. Funnily enough, the Hitman Triple Pack which hit PS2s also was free of that game, although certainly not in HD. The likely reason for continuously omitting the first game is that it was a PC exclusive.
This collection will be available for both 360 and PS3. The price is set at $40 on the listing, which is on par with other HD collections. Then there is the possible date of January 29th. It seems pretty close considering Square Enix has not announced anything officially, but then again, it could be a simple placeholder.