Has public Wi-Fi outlived its usefulness?

Over the last few years, public restaurants, coffee shops and other places people gather have added the luxury feature of free Wi-Fi. This has turned many a Starbucks into an unofficial office for workers and college students alike who might otherwise not have Internet access. These days, though, that luxury is becoming more and more useless. Many access points installed in a Starbucks, Subway, McDonald's or perhaps public library haven't been updated and are still offering 802.11g performa