Choosing between 11g and 11b at first glance is a choice of
speed, 54 Mbps or 11 Mbps. There are other considerations, however. Certain
products will work only with Mac OS 9 and others will work only with Mac OS
X. Also, a faster home network does not necessarily mean a faster internet connection,
as can be seen below.
Connection Speeds

This comparative bandwidth chart illustrates the
fact that while 802.11b has five times less bandwidth (i.e., five times slower)
than 802.11g, it also has about seven times more bandwidth than your average
broadband internet connection. Both 11b and 11g allow for much faster speeds
in computer to computer transfers within your internal home or office network
than a typical broadband internet connection allows for in internet transfers.
This means that in most cases, for the purposes of internet browsing and downloading,
11b can support maximum speeds just as well as 11g can.
Most 11g products are backwards compatible and will work with 11b networks,
but at 11b speeds. So if you have an 11g access point and an 11b wireless card
in your computer, your network will work at 11 Mbps. If you add a second computer
with an 11g wireless card to this setup, it will work at 54 Mbps while the first
computer remains at the slower 11b speed.
AirPort Equivalents