Longer would have meant sure death.
What I think Sony should have done... Forget Blu Ray, make an updated PS2. Keep all the specs for the PS3 now, but not the Blu Ray and just use DVD. Companies could use multiple discs if they had to.
This would have allowed them to release earlier and for a cheaper price. Less money spend on R&D as well. They could have launched before MS got a year headstart at $300 per system.
They would have sold tons cause there was no Wii, noone cared about Nintendo (well I did, but 99% of gamers didnt), noone knew about the Wii. Sony has the brand name and a cheaper system than MS with more games...
But instead since Sony is trying to win a format war (which has nothing to do with their game division) they tried to use the PS3 to support their Blu Ray format. If it worked it would have been great for them, but it backfired.
They missed their launch date, MS got a huge headstart, they got a crappy price (even with losing money on it) and the Wii was an unexpected smash hit.
Its almost as if Sony went to an expert and asked "what can we do to $#%# up every day in every thing we do?" then followed that advise...
But a later launch and noone would even care anymore.