It occured to me that PS4 could be announced this year but not released until next year O_O
Could be wrong, just talking out of my ass, but PS3 was announced in 2005 and released in 2006. PS3 was actually initially planned for a Spring 2006 release but delayed to fall.
Seeing as how PS3 hasn't yet reached the magic 199 price point, it would essentially cut those sales legs short if PS4 did release this year.