According to Bikepedia: 2010 Trek 2.1 Triple - BikePedia

You should have a 50/39/30 chainring now and a 12-27 cassette. Do you use the 30/27 currently?

The typical compact double arrangement would involve dropping your 30 ring, swapping the 39 for a 34 and going to a 11-32 cassette to make up the loss of the small ring. You'd end up with a 50/34 chainring and 11-32 or 12-32 cassette for a 34/32 low gear

So, you'd get slightly larger jumps on the cassette and nearly the same lowest gear with less chainring shifting.
But... On the triple, you may be able to go lower than a 30 chainring and could definitely get the same lower geared cassette as a compact double if you need lower gears than what you have now.