Polluted,
Your owners manual is correct. Chevy put in a different engine (ecotech) in the 2009+ model years, in the US at least. This engine had some improvements and redesigns that have apparently fixed the timing belt issues.
Also, unless you are planning on doing the work yourself, anticipate a higher bill for the timing belt job.
Frankly, having looked at the labor required for my 09 Aveo and the damage that can happen if it's done wrong, I'd rather pay someone to take the responsibility.