We always try to tread carefully when too-good-to-be-true game release schedules, like the recently leaked PSN list, start to appear on the internet. On the one hand, we want to get you this potentially juicy information as quickly as possible. On the other hand, these leaks are often based on sketchy information that can end up being highly variable and misleading to the average reader.
Sure enough, that's basically what Sony said by way of addressing the leaked list. In a statement reprinted by Eurogamer, the company teasingly tells us that listed content like "Ratchet: Quest for Booty" and "Dark Mist" "may be working titles or placeholders subject to later confirmation." Similarly, dates for everything from Super Stardust DLC to Home are officially "not confirmed until issued as part of a press release or formal announcement." So, to summarize, while the list itself is probably authentic, the information contained within it should be considered "subject to change" at best.