"It's tough to handle this fortune and fame
Everybody's so different, I haven't changed"

-- "Life's Been Good To Me So Far," Joe Walsh, 1978

If you haven't looked at Citrix Systems (Nasdaq: CTXS) in a while, you might wonder what the heck happened to the networking software specialist's flagship products. Don't worry -- MetaFrame and Citrix Presentation Server live on today; they're just hiding behind a different name.

A cursory glance at the latest earnings report from Citrix should be enough to convince anybody that the XenSource virtual computing platform is taking over the entire company. The XenDesktop product line, which is a direct descendant of the old MetaFrame application hosting platform with a hearty helping of Xen virtualization trickery, represented four of the five largest transactions for Citrix during the first quarter. Driven by 18% year-over-year growth in cloud computing solutions and support services, total revenue came in at $414 million, or 12% above year-ago levels. Non-GAAP earnings jumped to $0.40 per share from $0.32 per share.

And the future strategy is all about the Xen brand. Citrix has entered a partnership with industry giant and longtime Citrix collaborator Microsoft (Nasdaq: MSFT) to accelerate the business of desktop virtualization. For those unfamiliar with that concept, the idea is to host your desktop environment on a central server, to which you can connect from anywhere with a lightweight system of your own and leave the heavy lifting to that beefy server. If that sounds like a great job for netbooks and tablet computers, you're exactly right -- Citrix happily brags about its numerous best-selling client applications for the Apple (Nasdaq: AAPL) iPad tablet, for example.

Other virtualization vendors like Microsoft, Red Hat (NYSE: RHT), and VMware (NYSE: VMW) can do many of the things a Citrix Xen environment does, of course. But it's a fragmented market where Citrix has found a comfortable niche of its own. As CEO Mark Templeton explains, "the greenfield opportunity is really the overall desktop virtualization space, which is where we are being broadly successful without seeing VMware frankly a whole lot." Through a long legacy of MetaFrame experience, Citrix has done that sort of multiple-user, piecemeal virtual computing with an unrivaled history.

So Citrix is doing a better job than Joe Walsh ever did of moving into a future of pervasive cloud computing where the competition is heating up faster than a gas-fired oven. And don't forget that the Amazon.com (Nasdaq: AMZN) EC2 cloud computing service is built on Xen virtual machines from Citrix. As Amazon leaps forward, in other words, Citrix is sure to follow.