Nextel has the advantage of TCP/IP stack already built in (Public MDS/MDG). Already works with Internet applications such as instant messaging, chat software, telnet/SSH.
Also permits static IP addresses to be assigned directly to the devices for an additional approx $4 per month. Nextel is one of the few networks with native TCP/IP at the wireless network level without NAT/gateways being necessary. You can't get a static IP address from any other carrier without getting BES/MDS -- celltower changes and coverage going in-and-out can change IP addresses and disrupt instant messaging and telnet/SSH sessions.
Coverage is good in some areas. But in other areas, you may prefer another carrier such as CDMA or GSM. And you pretty much can't roam outside of North America if you stick to the iDEN network.
Above and beyond what Mark had mentioned the Nextel Blackberry's offer a speakphone which is very well done and PTT (Push to Talk) although I would like to see the PTT button on the side of the device instead of the top it's another added feature.
>>so would i be ok in saying that you dont need webmessenger for AOL chat....because you have the IP stack...?
WebMessenger is separate from the IP stack. The IP stack is the thing that "enables" the Internet on your BlackBerry that WebMessenger requires. Some people need to purchase BES/MDS hosting in order to enable IP stack, but the elimination of this requirement that Nextel has an advantage. It's the BES/MDS hosting that you don't need with Nextel.
If you want to chat, then you do indeed still need a chat program such as WebMessenger or one of the several others.
But WebMessenger won't work if your BlackBerry does not have Internet capability. (BlackBerry needs a method of Internet connectivity -- such as Nextel TCP/IP, or Public MDS, or hosted MDS, or BlackBerryOS 3.8+ running on BWC 4.0)
The Nextel blackberry has an excellent Speakerphone (already mentioned) - it is so good that I can leave my phone on my desk or dashboard and still hear and be heard where no other phone has been able to give me that.
The PTT feature is nice if you know others with nextel
The Antenna - ugly as it may be provides a 3dbm gain (so I read) and is such a help I can go from 1 bar to 5 bars by raising the antenna.
However the nextel blackberry is on the nextel network, so if you know someone in your area with nextel you may wich to talk to them about their coverage and satisfaction. On the plus side I have had excellent luck with their technical support and customer service.