I've been playing with this new toy for a week now. I'm actually quite impressed. The promised features are there - 802.11b WLAN, GPRS/EDGE, new PC Suite, Symbian 7 (S80 DP2.0) with MIDP Java, 80BM RAM, 128MB MMC included... But no WCDMA though.
I was surprised how well the WLAN support works. The phone allows you to define a priority list of WLAN and GPRS access points. All Java and Symbian applications are automatically compatible with WLAN, even if they were originally developed with GPRS in mind. The phone detects WLAN networks automatically and falls back to GPRS when they're not available. EGPRS (EDGE) is quite fast.
MIDP Java support works fine. Many applications, if coded smartly in the first place, are quite compatible. The main problems are with the resolution (640x200) being a bit unexpected for programs that were originally designed for 176x208 or 128x128. And of course the menu buttons are not where an S40/S60 application would render them.
The disappointments are there too. Nokia's VPN support is closed and proprietary. It is supposedly based on IPSec, but you need special Nokia server software to use it. Come on! Just let the client connect to any generic IPSec (or PPTP) server and we'll be happy.
The long awaited availability of WLAN is just screaming for a Symbian VoIP client, but there seems to be none available. I really wish someone would make a simple, generic SIP softphone for Series 60/Series 80.
One might wonder why Nokia put 802.11b in the phone when 802.11g is already in widespread use. I suppose it is because the phone can only handle about 1 Mbit/s of traffic anyway (when downloading and saving a file), so ramping up the theoretical maximum speed from 11 Mbit/s to 54 Mbit/s doesn't really serve a purpose.
Anyway, in conclusion, the 9500 communicator is a major upgrade from the 9210, which didn't have basic stuff like GPRS and Java. On the other hand, if you don't need that stuff, you might want to upgrade just to get a newer and better PC Suite. It has synchronized my calendar and contacts fast with no problems so far.