Even as Linksys, Netgear, and Belkin sell routers and wireless network cards based on a mere draft of the eventual 802.11n Wi-Fi specs, that standard remains uncertain. The IEEE committee assigned to ratify such things failed to move the current 802.11n spec forward for final approval. All of those pre-802.11n routers already in the field may have been launched prematurely, critics warn. As no one knows for sure what shape the final 802.11n spec will take, it’s increasingly unclear whether a firmware upgrade will make the pre-802.11n routers truly 802.11n compatible, let alone interoperable.