Getting Some Pathfinder On

So it has arisen that I may be participating in an upcoming Pathfinder (d20) jaunt through the Rise of the Runelords adventure path. As someone who hasn't played anything d20 in nearly a decade and hasn't played Pathfinder ever, I'm a bit shaky and wanted to probe the hive-mind for a couple of things (and hey, this forum does say it's open for chatter about non-SJ games...)

1. Any particular classes or options that people familiar with Pathfinder would steer a beginner/unfamiliar player towards? I've been considering taking a stab at the Gunslinger class, but since I don't know much about the system (in particular, the details of classes and ways that it differs from 3.5 D&D), I'm mostly making that decision on the basis of "Oooo boomsticks." I just want to make sure that if I go down that road (or any road) I won't be unknowingly handicapping myself and the party. If Gunslinger should be in the "Beginner No-Go Zone," what are some recommendations?
   
   
   


2. Anything about Pathfinder that, as someone who's only familiar with the D&D 3.x side of d20 (and d20 Modern, but that doesn't seem pertinent), I should be aware of / look out for? Glaring rules changes? Shiny new things that I'll want to make sure I take advantage of?

As always, the wisdom of the hive-mind is much appreciated.

Getting Some Pathfinder On