Here's some details I pulled off of Verizon Wireless' site.

With 2 year contract: $269.99 - $70 online rebate = $199.99
With 1 year contract: $339.99 - $70 online reboate = $269.99
With No Contract: $489.99

The 1 year pricing actually isn't that bad, if you assume that you'll be enticed to go to another device in a years time - especially if you'll have to switch carriers. (Palm Pre 2, iPhone 2010, I'm looking at you.)

It looks like Verizon values a 2 year contract at $290. (489.99-199.99) They also value a 1 year contract at $220. So even assuming you'll go to the BBxx30 on Verizon in a year, you may save some serious dough down the line if you pony up the extra $70 now.

I'll probably go with the 2-year contract, because there doesn't appear to be anything great on the horizon for VZW and it'd be unlikely that I'd switch carriers.