Mike,
One thing to remember: At Apache the "incubating" status has NOTHING to do with the quality of the code or whether the code is "production ready" or not. It is entirely related to the status of the community. I've added some information about that to our FAQ:
http://cwiki.apache.org/CXF/faq.html
That all said, there are people using CXF in production environment and others getting close. Unfortunately, I cannot say who (due to NDA agreements and such). That said, Apache CXF is used as a core part of some commercial products such as IONA's Artix (caveat: I work for IONA) so you can pretty much assume those users would be using it in production. (although supported through IONA)
Dan Kulp
daniel.kulp@iona.com