As is usual with the internet, there seems to be a lot of misinformation that is so oft repeated, it eventually becomes fact. For that reason, I'm going to make a few quick points on Killzone 2's development because it deserves to be corrected and incorrect information, never repeated.
The fallacy in question relates to Killzone 2's development time.
Just because that CGI trailer was shown in 2005 doesn't remotely mean development had started on the game. The trailer was outsourced to a Scottish company (I believe) who deal with promotional CGI trailers. At the time, the game was known as "Killzone PS3"
Now, you may remember, before it was released, Killzone Liberation was called "Killzone 2", and this may be where the confusion stems from. In 2004, an IGN editor visited Guerilla Games. The article mentions that, in 2004, Guerilla had no intention of releasing what was then called "Killzone 2" on PS3. Sometime between August 2004 and May 2005, Guerilla recieved dev kits for a new system. The PlayStation Portable launched in North America in March 2005 with "Killzone 2", now titled Killzone Liberation, following in October 2006.
One key thing to note at this point is that they didn't even get their PS3 dev kits until after summer of 2006.
The development time, though, as stated by Guerilla on the PS Blog, in their 2nd Live Q&A session, was 3.5 years total, 2 years full production.
People continue to claim Killzone 2 took 4 to 5 years to develop. This is not only ridiculous, it's also completely impossible. That would put the start of development would put it in 2004-2005. The final PS3 dev kits, the ones Guerilla were given, weren't even available until summer 2006. Assuming Guerilla are correct, full production didn't start until after Killzone Liberation had launched.
Basically, it seems like people are attributing the development cycle of both the PSP and PS3 game to the same title.
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