Chrysler 300 3.5L V6 it will not turnover.

Yes

Has the timing belt been replaced according to the recommended scheduled? Now many miles on vehicle?

Over 150,000 miles and unsure

Over 150,000 miles and unsure

While cranking the engine - does it seem to be spinning faster or just sounds different than normal?

Too me it sounds normal, just not turning over, but I could be wrong.

At this point the only y thing to do is test - ignition spark - fuel pressure - and compression... One or the other is not up to par .. Don't know your skill level but you may have a car repair buddy that'll help.. Too damn hot to be working on a vehicle anyway .. And I'm in VA. Good luck with it!

Not going to cause a no start condition but here is an informative link : http://www.autocodes.com/p2008_chrysler.html