Where a heterogeneous environment years ago may have been multiple Unix systems, today it could include two or more types of hypervisors on x86 systems. In the cloud era, being heterogeneous will mean using multiple clouds for compute and storage.

Even Hewlett-Packard, at its big user conference here this week, bowed to that reality, and announced it would support Amazon's hosted system as well as its own through its systems and services.

"We're not here to force anyone to one (cloud) bursting provider, we're about choice," said Scott Weller, HP vice president and general manager technology services support.

Hardware environments that mix and match multiple vendors are also important to some users.

Hector Fuentes, a storage administrator at a communications industry firm who was at the HP conference this week, believes that by using different storage vendors in his environment he can leverage them "for better pricing, better tools, and better support."