It's great to be able to download podcasts and listen to them in the street using a bluetooth headset.
I can also watch Sky Mobile -- but I got bored with that after about 5 minutes. (Why does the Discovery Channel only show 5 minute tasters of programmes, instead of full programmes?)
The IMAP email client gives me push email.
I have even found an ssh client so if there's a real emergency on one of the servers I deal with, I can just about work on them from the beach/bush, as long as there is a GPRS signal.
I have a 1 gig card in it which means I can record my choir practices and go over the trickier passages later on. (I might even create a podcast for the other choir members ... )
The bad ... every so often I have to reboot my phone because it's frozen ... and it takes ages ...
Battery life is also bad, especially when Wifi is on for any length of time. But that is just basic physics ... conservation of energy and the second law of thermodynamics.
I just have to think of it as a 'palmtop' computer that, by the way, acts as a phone.
The ugly ... the keypad slides down from the bottom. They could easily have had it slide out from the side and put a full qwerty keyboard on it. Considering that it's a computer that also does phone calls, this was a bad design move.
I'm ambivalent about the OS (Symbian). I do prefer Palm OS, and I do prefer the Treo to the N80. However, I was given this phone by a client ... and an N80 in the hand is worth a dozen Treos in the bush.
Final word: although it's great as a wifi phone, I still much prefer my cheap Nokia 2118 as a GSM mobile phone. http://store.vodafone.co.nz/mobile_details_summary.aspx?ptrecno=1987
It boots rapidly, holds its battery charge for days, and just behaves as a phone, reliably and predictably. It doesn't claim to do anything else.