The goal of mobile Wi-Fi is, of course, mobility, but seamless connectivity for users who wander about isn't always completely seamless. In a world where roaming delays exceeding 100 milliseconds aren't tolerated (wireless voice), and where giving up on one access point before finally finding another can take up to 5 seconds, users should take such delays into account when deploying wireless LAN applications.
Via [wi-fiplanet.com]