You know, that's actually a pretty interesting concept that deserves some consideration, if you ask me.
No it's not.
One of the "metabolites" of Caffeine is Paraxanthine, which increases lipolysis. This increases the levels of free fatty acids in the bloodstream, allowing for increases fat burning.
Paraxathine is actually the highest metabolite concentration for caffeine.
Caffeine isn't really a "stimulant," it's more of an anti-suppresant (made up word). It antagonizes adenosine.
While adenosine might be fun for seeing what type of arrythmia you're in (Jeff, you're a PT, right? You've probably seen adenosine used for this)....it is the opposite of a stimulant.
By blocking adenosine, a stimulant effect is placed on the CNS.
The act of "burning" caffeine increases the amount of fat used for energy and stimulates the body, resulting in greater caloric expenditure. If this is bad for metabolism, the anatomy and physiology books need to be re-written.