I was reading on Engadget that the evo has been rooted prior to its release. Looks like incredible lost. Hope root comes soon.
I don't think the "source code" is available, I could be wrong. HTC posted something on Facebook and Twitter about giving everyone the source codes for the Incredible, Evo, and some other phones, but I didn't see the Incredible in the list.
This is HTC's post on Facebook