I use Illustrator for wire framing. It seems to provide more versatility for me. I don't use any online services although I have looked into a few of them. While they can be handy to share brainstorming ideas, they can be equally hindering in the completions of the framing stage (allowing too many to continually adjust). And, I own Illustrator, I've never seen a reason to pay additional fees for such a simple thing as wireframing.
And I've created my own browser frames in Illustrator which are an amalgamation of common aspects between all the browsers. These can easily be pasted into Photoshop as smart objects should the need arise.