I'm a hypnotherapist and often use EFT with my clients as well as for myself- I think it's amazing!

Personally, it has gotten me over fears in social situations, fear of heights and I often use it as a tool for working through "lingering emotions" (for which it works about 50% of the time). As for with my clients, it's helped with past traumas, body problems such as Tinnitus (ringing in the ears) or sexual problems - you name it!

I find that the toughest obstacle with EFT is staying, as Gary calls it, "Tuned-In" to the problem - Especially for a person just starting to use the protocol. The way EFT works is that you have to maintain the disruption in the energy system (or more clearly, you have to be feeling the negative feeling or thinking the negatve thought - To at least SOME degree) while tapping. That can be a bit hard as our minds often tend to think about other things.
I think it is that reason why some people don't get as good results as others.

In conclusion - It is awesome and HIGHLY recommended!
Good luck!