As a matter of interest to me, how many LQers are Linux for z users: admins, programmers, etc.?

Not a lot from what I've noticed. There have been a (very) few zLinux specific questions.

For a short time at work I was administering a proof of concept installation of Linux for zSeries. (Suse, actually.) The guy who was handling the z/VM side left, and that particular POC fizzled out.

Since then I've attempted to drum up interest in acquiring a RHEL license to give it another, more deliberate go. Mainframe + Linux instances seems like quite an attractive pairing to me.

We've been running Suse for 3-4 years in production, mostly for portal-type applications like DB2 Connect, etc. Although we haven't put much in the way of demand on it, Suse under z/VM has been a very stable platform.

Now that we have a z10 (and the facilities folks are reporting power consumed by group), the distributed group is showing some interest in migrating. They're Red Hat oriented, however, and we may have to switch distros.

Pricing seems to be another attraction factor although I'm fuzzy on the numbers there. Good luck getting something going. It's been a long road at my company.