I loved this episode, Caitlin was adorable, Cisco was a badass (dat Vibe reference), Piper continues to amuse, Peek-a-Boo was flat, but her powers looked amazing and it seemed like a nice intro for a character with potential. Barry and his dad were great, too. I don't know how I feel about Linda, though I'm predisposed to like her because I love the Malese Jow's character from the Vampire Diaries (though I'd rather keep my teen love triangles in that show and not this one). Iris meh.
I really hope that this show can learn from Arrow that pushing comic book canon is not always the way forward. Caitlin is awesome, and I get that she's supposed to become Killer Frost, but I really hope that they don't just do a Slade and have her go crazy, especially since they won't have Mirakuru as a (weak) excuse for lazy writing.
Honestly, I hope they go for a more Plastique-like route where she starts off dangerous because of her need for heat (I believe that's her power/problem, she is constantly cold and needs to syphon heat). That would also allow Firestorm to be the solution, since he's a constant source of heat (another comic book arc, I think). Basically, I don't want her to go evil just for canon. If they can find a good reason and they can earn it, maybe, but otherwise it just feels contrived.