See the thread that I started, named "Adios, Cingular!" for my own
experiences with being strong-armed into dropping my ATTWS plan.

Let's review a little bit of history:

AT&T Wireless, and the spun-off company ATTWS, always allowed their
customers to remain on discontinued plans, as long as they continued to pay
the bill every month, for as long as they chose.  Once a plan was withdrawn,
those "grandfathered" customers were no longer able to add lines or optional
features to their plans, but they were welcome to continue them as they
were.

When the ATTWS-Cingular "merger" (translation: "Buyout") was announced,
ATTWS made it clear to their customers that they would not lose any of their
existing rate plan perks when the new company assumed control.  And, in
fairness to Cingular, they kept their word.

But Cingular took advantage of changes in technology to coerce the ATTWS
customers into "upgrading" to more expensive CIngular plans.  For one thing,
they refused to sell TDMA phones anymore.  Sure, as long as one's present
phone kept on working, one could continue to use it.  But if the phone was
lost, damaged or stolen, Cingular would not help.  All they would do is to
try to convince the customer to "upgrade" to the current GSM plan.  Sure the
customer could try to buy a phone on eBay, but that took time, and most
people did not have the foresight to buy a spare phone for such emergencies.

Even the ATTWS GSM customers were screwed, because Cingular would not
replace their SIM cards or handsets with any but Cingular
products--essentially forcing customers to "upgrade."

Finally, Cingular made it clear to ATTWS customers that there would be no
further improvements or enhancements to their equipment or to the Blue
Network itself.  Those of us that hung on were, essentially, trapped in a
time warp.  We had what we had, but we weren't ever going to get any
more--unless we agreed to cast off all the freebies that ATTWS awarded to
us, like free incoming text messaging, bonus Anytime Minutes, free M2M, 7 PM
nights/weekend start times, and unlimited night/weekend minutes (several
Cingular plans were limited to 5000 n/w minutes).

Then Cingular began cutting back on the TDMA towers, resulting in many of us
experiencing high numbers of dropped calls or "No Service" displaying on our
phones.  It typically took 2-3 minutes for my Ericsson TDMA phone to display
"Cingular" after I turned it on.  Until then, I could not make or receive
calls.  Great in emergencies, huh?

My Panasonic Versio TDMA phone began shutting itself off whenever I drove
beyond my home area.  I would turn it back on, and it would take 2-3 minutes
to find a Cingular signal.  It would remain on for perhaps 10 minutes, then
shut back down again, requiring me to repeat the exercise.

How was I supposed to keep checking my phone, while driving, to see if it
had gone off?  What good was a phone that was turned off, making it
impossible to receive calls?

None of these things happened until Cingular took over.

A couple of weeks ago, I switched to Sprint.  Got three free phones.  No
activation charges.  Online billing.  Free M2M.  N/W starting at 7 PM.
UNLIMITED N/W minutes.  Crystal clear sound quality, relative to my old TDMA
phone.  And a monthly price for 3 lines that was about $10 less than what I
was paying to ATTWS/Cingular!  A nationwide home rate area, rather than the
regional home rate area that I had with ATTWS.

All I gave up was free incoming text messages.

I've called Sprint Customer Service 5 times, to port one of my old numbers,
to reassign one of my phones to a preferred area code, to ask questions
about roaming rates, and, today, to change the Caller ID information on each
of my phones to display the name of the actual user of each of the
respective phones.  My TDMA phones couldn't do that.

In every case, the reps were knowledgeable, courteous and friendly.  More so
than the Cingular reps that I've spoken to over the past year.

Life goes on after Cingular.  I feel really good after parting company with
them.  They may boast that they have the largest network, but my needs are
much less demanding.  All I want is a carrier that doesn't drop my calls,
and that doesn't play around with the network so as to deny me the service
that I pay for.  Oh, I almost forgot--and I'd like my carrier to give me a
modicum of respect for being a customer for nearly a decade--rather than
treat me like some piece of garbage that just rolled in off the street.

Sprint treated me better on my first day than Cingular did on my last day.

ADIOS! Cingular.

Same thing happened to me. I told them that I would accept a monthly credit
to my account for the use that I did that would have been included in my old
plan. They forwarded my call to a "customer resolution" specialist. She was
able to reinstate the plan and as an extra she asked if I would like it on
any other phone I had on the family plan. As we all use Media Net and SMS I
took it on all my phones and dropped other features. End result, Saved me $4
per month with more than I had before.
I have always had a good experience with Cingular and see no changes in the
future. I guess it is how you approach the situation and the attitude you
display.