A question that is on many WLAN buyers' minds is whether to make the move to draft 802.11n gear. There's a lot of it out there and prices are even reasonable (at least for wireless routers, not adapters)—in some cases not that much more than 802.11g gear.
But the IEEE Task Group n is still making changes to 802.11n and there are no guarantees from any networking product vendor that the gear you buy today will be upgradeable to the standard when it is finally approved in mid-2009 (by the current schedule).
And even if your current draft 11n gear were upgradeable, whether you would want to upgrade it is another question. Some chipmakers are into their second generation of 802.11n chipsets and will likely be into their third or fourth by the time 11n is released. The biggest push is to reduce cost, but performance improvements are also probably quietly being worked in.
The other question is when upgrades would be available for the stuff you're using today. If past upgrades are any indication—WEP to WPA, WPA to WPA2, WPS—your gear might never make the cut. No matter how large the company, resources aren't unlimited. Pumping out new products is usually where the time and energy goes because it brings in new revenue. Fixing old stuff just isn't profitable.
Purchasing from a "name" vendor doesn't seem to raise the odds that you'll be upgraded, either. Just look at Linksys' popular WRT150N. Even though it was born with a WPS pushbutton perched proudly on its top cover, Linksys appears to have no plans to add WPS support. Heck, they haven't even fixed the fact that it defaults to Auto 20/40 bandwidth mode (due to a now-closed hole in the Wi-Fi Certification process) instead of the 20 MHz mode that is a Wi-fi Certification requirement.
But enough of my complaining. What should you do if you're thinking of buying draft 11n gear? Up until now, I have recommended moving to dual-band when moving to draft 802.11n. The reason for this was to provide the option of accessing the relatively uncrowded 5 GHz band to escape interference from neighboring WLANs. The 5 GHz option provides 8 - 12 non-overlapping channels vs. the three you get in the 2.4 GHz band.
Those extra channels not only provide more options for avoiding your neighbor's network, but are also needed to take advantage of 11n's throughput-boosting channel-bonding mode. Enabling channel bonding (usually referred to as Auto 20/40 mode in draft 11n router configuration interfaces) in the 2.4 GHz band takes up two of the available three non-overlapping channels (1, 6, 11) and usually means that you'll be interfering with neighboring wireless LANs. This is why the Wi-Fi Alliance requires that draft 11n routers default to 20 MHz bandwidth mode in order to be Certified. And some companies, such as Apple and Intel, have locked out 40 MHz mode in 2.4 GHz altogether in their draft 11n products.
But the industry has been slow to produce dual-band gear and dual-band, dual-radio products, in particular. And the relatively few products they have produced command prices ($150 and up) that cause most consumers to give them a pass.
So I'm changing my recommendation.