http://www.indianvideogamer.com/2010/11/november-24-release-date-for-gt5/
Some things to consider:
1. Before you question the source, this was the same site that announced the GT5 Signature Edition.
2. The initial announcement of the delay came from some random Russian blog that reportedly got the info from Sony's Russian distributor, so this isn't at all implausable.
3. Sony has re-scheduled the game's Madrid launch party for November 23rd, the day before.
I think this is the real deal, guys!