Had a Samsung Omnia for a week, but just sent it back. Mainly cos it kept crashing and I bought it sim free and when it arrived it wasn't a UK model. I'm still unsure myself what to go for now. Another Omnia, the Blackberry Bold, iPhone 3G (which I like a lot, but not sure if I can cope with all the stuff it doesn't do!) or the soon to arrive HTC Touch HD. Will probably wait now until the latter comes out before I make my decision.
I quite liked the Omnia, the home screen (not the widgets one, cos that was rubbish) was good, had my email set up so I could see when a message came through, multiple accounts too and it was just a screen tap away to read them. However, when I actually wanted to make a call on it, it did take me a while to work out how to search the phone book! Hubby just stood there laughing at me! Didn't want to update the ROM or mess too much with it because I wasn't sure I wanted to keep it (hence not fixing the crashing thing), but it did look like the Sky's the limit with what you can do with it.
Have to admit though, after all the bells and whistles, it was nice to go back to the uncomplicated life of my N95. Guess I'll also be checking out the N96 too!