How will migrating from .Net 3.5 to 4.0 affect my WCF components?

From your own personal experience, how much of an impact will migrating to .Net 4 have on my existing WCF components?

Is there a big开发者_如何学C risk that I may need to re-write a lot of code?

I was worried about the same thing- we have a large system with about 50 services/contracts across several bindings with some complex config and custom bindings/behaviors. I migrated the whole thing over to 4.0b2 and ran everything with no problems whatsoever. They've done a really good job of preserving backward compatibility where things have changed. I haven't seen a list of breaking changes from 3.5 to 4.0 yet (only between betas), but I'm sure they'll publish one at release.

Good luck!