Please confirm: Is Windows Workflow Foundation a good horse to be backing right now?

Question

We are in the process of selecting a workflow solution for a company that uses Microsoft products end to end. Given the news on WF4, in that it seems to be essentially a rewrite

Answer 1

Maybe it is a little late for you, but now that WF 4.0 is released in beta, other people thinking the same question can consider backing the 4.0 horse instead of 3.5 horse.

This goes some way to fixing the following problems:

•The workflow designer will drive you insane because it is so slow (in certain circumstances) and re-arranges your state machines as it sees fit. [Designer Perf Improved]

•Its not easy to unit test them. There are ideas out there but none seemed particulary easy when we started this WorkFlow Unit Testing [I think it's a little easier now, some of the introduction to workflow samples include plenty of unit testing]