The generation Wi-Fi standard is still far from being finalized, but devices built according to the draft specification are becoming more and more available - not only from Wi-Fi hardware manufacturers. Dell is the latest vendor that has begun offering an optional wireless draft-n card for "select Inspiron" notebook models and its XPS notebook line.
Dell says that the card, which is based on Broadcom's Intensi-fi Draft-N chipset, supports data rates up to 270 Mb/s, versus the theoretical maximum 54 Mb/s of 802.11g. Real world applications however may not be able to take advantage of the extra bandwidth. A recent review of such devices at Tom's Networking unveiled that draft-n may in fact be slower than 802.11g network connections under certain circumstances.
Dell offers the "1500" draft-n card for $60.