I've heard that Verizon Wireless supports Enhanced Messaging Service (EMS)
but only between it's own customers (i.e. Verizon to Verizon not Verizon to AT&T, etc). If you've ever sent/received a SMS message between 2 non-smartphones on Verizon, you'll notice that you can insert a small animation that will be received by the other party. I think EMS will automatically break up long SMS messages into multiple messages. The 160 character limitation on the Blackberry is definitely a device limitation, however if you try to send a message longer than 160 characters from Verizon to a non-Verizon customer, you will get a warning message back telling you that only the first 160 characters will be sent to other party.