PC cards and base-station chipsets that support the Wave 2 mobile WiMax specifications are now starting to be unveiled by silicon vendors like Sequans Communications and Picochip (See PicoChip Intros Wave 2 WiMax.)

Here's why you should care, even if only a little:

Rollouts: Wave 2-compliant products will drive the rollout of mobile WiMax in the U.S. by Sprint Corp. (NYSE: S) If this silicon had somehow been delayed, that would have been bad news for the third-ranked cellular operator in the U.S. (See Sprint Facing WiMax Delays?)

The Reston, Va.-based operator was rumored to be a driving force behind the WiMAX Forum 's Wave 2 specifications, which mandate chipsets that use "beamforming" and multi-antenna arrays to increase the data transfer rates and capacity offered over the network. (See CTIA: WiMax in the Air.)CTIA: West Talks WiMax.)

Aside from smaller deployments by Clearwire LLC (Nasdaq: CLWR) and Towerstream Corp. (Nasdaq: TWER), the Sprint rollout will be the first real test of WiMax in the U.S. I have no doubt that many other vendors and operators will be watching the user numbers with intense interest.

Buyouts: The success -- or otherwise -- of Wave 2 will also likely affect the fortunes of many of the silicon startups working in this market. As far as I can tell, Beceem Communications Inc. , PicoChip, and Sequans are the three leading silicon surfers of the second wave. If the technology takes off, I expect one or probably more of these firms will see a happy exit, either through acquisition or IPO.

If the applications allowed by Wave 2 don't grab the public's fancy, however, then the entire WiMax edifice could come crumbling down.

Flameouts: Broadband research firm Maravedis claims there are nearly 1 million WiMax users around the world. Most of them, however, are still using pre-WiMax or fixed networks.

The first true mobile offering -- the WiBro networks in South Korea -- doesn't appear to have attracted many users yet. In fact, operators have struggled to sign on even a couple of thousand subscribers since the service was launched in 2006. Poor coverage and a lack of suitable handsets have been cited as reasons for the slow uptake. (See Samsung's New Support for WiBro.)

No doubt Sprint is keen to avoid any WiBro-like missteps.

— Dan Jones, Site Editor, Unstrung