Agere is latest to offer faster, quasi-proprietary extensions to speed its Wi-Fi chips: Of course, the faster speeds aren't Wi-Fi because they're not tested for interoperability nor would they pass most interop tests. Agere's "150 Mbps" uses a variety of techniques, the most interesting of which is client-to-client transfer in which an access point is ignored in the interests of higher speed when possible.
Most of the major chipmakers now have their proprietary packages; some are already offering the firmware upgrades, while Agere is pre-announcing a fall delivery. (Linksys just announced the faster version of their flagship Wi-Fi gateway.) Fall is key in that 802.11e is expected to be ratified by then, and many of the proprietary extensions will be tweaked to comply with that standard.
Atheros also announced their Dynamic Turbo mode update today: This mode sits on top of their other Super G (non-Wi-Fi) extensions and is the disputed mode that Broadcom claims causes interference across the entire 2.4 GHz band for Wi-Fi devices. Turbo uses channels 5 and 6 simultaneously to achieve higher throughput. The Dynamic version listens for traffic and moves into the mode only as needed. Atheros claims 60 Mbps of net throughput with Super G including Turbo.
The short-term push for speed is all about marketing: who can put the fastest speed on the box even when that speed only works among like devices and has an actual net throughput of a fraction of the number on the box. The vast majority of consumers don't need more than 20 Mbps (the rough throughput of an 802.11g-only network), and businesses won't adopt this pre-standard equipment except in small offices.
The run-up to 802.11g's ratification involved lots of early distribution of a standard in flux, but manufacturers worked like crazy to continually update the firmware towards more compatibility. But even with that proviso, early 802.11g adopters faced mysterious problems, network slowdowns, and other hassles.
Is it worth the extra speed now instead of waiting for ratified versions of the underlying standards which will work across all devices by all makers? No. There's no home networking purpose that has that much bandwidth demand.
Tom Krazit of IDG News Service shares that perspective: More speed is grand, he notes, but how can consumers use it? His pithy summary: ...it's a moot point to millions of U.S. and European home users stuck with Internet connection speeds far below the bandwidth promised by new 802.11g products.