If you don't need what the MacBook Pro offers, just get the used MacBook, as long as it's a decent deal with decent memory. 2 GB is minimum these days IMO, but if usage is light then 2 GB is sufficient (for the right price). Another option is a refurb white MacBook. You get the full 1 year warranty with that.
BTW, if the MacBook Pro didn't have Firewire and a backlit keyboard, I'd buy the white MacBook.
In fact, that's exactly what I did. When the aluminum MacBook came out, it didn't have Firewire and the entry level model didn't have a backlit keyboard, so I bought a refurb white MacBook instead.
For the next revision, Apple saw the light and added Firewire and a backlit keyboard to all the aluminum MBPs... and dropped the price.
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P.S. I waiting on the same for the 11" MacBook Air. The current model is crippled. It will be nice to see it gain Thunderbolt and a backlit keyboard, as well as a better hinge and longer lasting battery.