GlassFish (the JEE 6 reference implementation server) has Apache Felix built into it at a very deep level. It's what allows it to load, unload, and reload various parts if its functionality at runtime. That at least shows that the concept is sound, whether commercial servers do it similarly or not.
The question is more "are there any payware app servers that do NOT use OSGi". Here is a list of those that I know that DO.
- Spring dm Server
- SAP Netweaver (moving)
- JBoss (building their own OSGi but that story seems to be evolving)
- Oracle (I can never keep track due to acquisitions but they definitely have OSGi based server offerings)
So this is pretty safe ground for enterprise infrastructure.
D'oh! I forgot to mention that Jetty is part of the Eclipse space as well. It does not use OSGi explicitly but they produce bundles that run in an OSGi system so you can embed Jetty in your OSGi app (and vice versa).