Now the question is: What happens to the DeadMansSwitch service if something were to happen to its maker? It's like we need to form mini multi-generational cults to keep human services like that going for as long as humans keep going until the point they stop.
I'd say the thing that makes Pidgin more attractive is the fact it's free, whereas Beeper is $10/mo (unless you host the entire stack yourself, and at that point you can't use the Beeper app). Granted, Beeper has mobile apps going for it.