Almost 1 in 10 say they've ended relationship by SMS:

Nine percent of Britons admit to dumping a partner by sending an SMS text message on a cell phone -- possibly signalling the beginning of the end for the "Dear John" letter -- according to a new survey.

Among those aged 15 to 24, the figure rises to 20 percent.
...
Two percent say they have used text messages to quit a job.

With that said... this is in Britian where SMS is much more popular than in the US... but I can't help thinking of a particluar Seinfeld episode. The one where Elaine wants to break up with a guy over the phone and Jerry questions here about how many dates they've been on... that after a certain point in time its too late for a phone breakup, and you have to do it in person.

So if a phone breakup is that bad... how bad must it feel to have someone break up with your via SMS? Having been dumped over the phone, I know exactly how I would text back if I were ever dumped using SMS. It would only take two letters... FU.