This is a pretty good snapshot, but nothing more, I'm afraid. The focus is right in front of the squirrel and the squirrel (cute as it is) blends into the leaves...
I really dislike photobucket so I use flickr now. It doesn't take away from the sharpness, too much!
It does help it pop - now you have to address the problem of the centered and small squirrel. Try a close crop, following the rule of thirds, and with the squirrel larger!
The crop is definitely an improvement. Before, it was a picture of the ground with a squirrel, now it's a picture of a squirrel. You might be able to go even tighter.
Another composition tip. The image would have been even better if you could have gotten lower to the ground. Everyone's looked down at a squirrel. It's much rarer to look at them at eye-level. Of course, he was probably on the move here, so that may have been difficult.
Samanax: Thanks for the tips, I'll check out those sites
KvnO: Yeah, this was actually shot at the zoo right after it had stopped raining, so I didn't want to get too dirty but I see where you're coming from, and thanks for the tip.