While the Institute of Electrical and Electronics Engineers (IEEE) is deadlocked in the process of approving the 802.11n standard for years, the Institute now presents us the 802.11r standard. The benefit: 802.11r enables devices to move from access point to access point with less than 50ms in downtime, even for authenticated connections.
In plain language: Future VoIP phones will not drop a voice call as often as they do with the current standard. Take a look at the current VoIP phone collection of Siemens Gigaset here:
Siemens Gigaset VoIP phones

(Source: www.dailywireless.org)