Add me to the "pick a range and worry on either extreme" devotees. But then I can gain/lose 2-3 pounds in a day according to the scale. That much scrutiny would make me crazy.
Everyone's suggestions were really solid; I'd only add that particularly when you first hit goal, it's still very easy -- even automatic -- to stay in a "dieting" mentality.
It takes a while to relax into a routine of watching your weight without giving it the sole focus or energy that "dieting/weight loss/term du jour" can or did.
I couldn't tell if you were freaking out about the weight gain -- it didn't read like you were, but you never know -- but the whole idea of "maintanance" gets much easier if you don't approach it with the same mentality that you did the dieting itself.
They're similar but very very different animals.
Grats and keep rocking it out!!!