802.11g is a Ratified standard. You do not see it too much associated with the term WIFI because Standard and WIFI is not the same thing.
On WIFI.
WIFI is a certification process. A company gives its Hardware to WECA and they test and certifies (or not). It costs a nice sum of money, and it delays the product introduction into the market. As a result most of the inexpensive Wireless Network Hardware companies do not take part in this process.
For cooperate setting, insuring interoperability is very important. You do not want people to get stuck and not be able to Log On to the Networks when they are roaming between buildings and various corporate sites.
802.11i Within a year.
It would be the same ?Speed? as 802.11g, the main change would relate to security.
Quote from Infoworld:
"The 802.11i draft now circulating is for a security algorithm called Temporal Key Integrity Protocol. Developed with the help of some of the encryption experts that exposed WEP's vulnerabilities, TKIP, like WEP, is based on RC4 encryption--but implemented in a different way that addresses those vulnerabilities, Eaton says. Among other things it generates new encryption keys for every 10 kilobytes of data transmitted".
Down the line 2-3 years from now there is a talk about 802.11h that should go to about 200Mb/sec.
Given Wireless loses it means that it would function at 80-100Mb/sec. like the current 100Mb/sec. Cable Network.