I just downloaded Skyfire – which is a new browser for windows mobile 5/6. I’d previously been using the beta version of Opera; which was annoyingly buggy.
I’ve only been playing with Skyfire for a few minutes – but I’m already impressed. It’s fast and, so far, hasn’t given me any problems. The user interface looks good and the fact that’s it’s named after one of the best transformers doesn’t hurt! 
It’s free and you can get it from getSkyfire.com