Robert LeBlanc, IBM Senior Vice President for Middleware, gave a keynote presentation at the Red Hat Summit. Here is the [26-minute YouTube video]:
I am running Red Hat Enterprise Linux (RHEL) 6.2 as my primary laptop operating system. Most of IBM's products, like Lotus Notes for email, run natively on Linux for the desktop. I have a Windows XP running as a Linux KVM guest to run a few third-party software that we are still using.