I hopefully will not see any of you in Chicago this weekend. I'll be spending most of the time in Wicker Park, so stay away.

There are actually five different mobile phone standards in use
in the U.S.

AMPS
TDMA
CDMA
iDEN
GSM

Further complicating things, there is 800Mhz and 1900 Mhz for CDMA,
TDMA, and GSM. Most CDMA phones will work on 800 MHz & 1900 Mhz CDMA,
plus 800 Mhz AMPS. Most TDMA phones will work on 800 Mhz & 1900 Mhz
TDMA plus 800 Mhz AMPS. There is no such thing as a CDMA+TDMA phone.
Most GSM phones will work ONLY on 1900 Mhz GSM, though there are
beginning to be some 800 Mhz+1900 Mhz models available, as well as
some world phones that add 900Mhz and 1800 Mhz. As I stated before,
there are a couple of GSM+TDMA+AMPS phones, but these are hard to
find and are not sold in all areas. They were developed to ease the
transition from TDMA to GSM by Cingular (AT&T Wireless has chosen
not to offer these phones even though they are making the same
transition).