I know the smell of a dying solution, and IM's got it bad. It's not dead yet, but it's got seven tentacles in the grave.
I came late to IM, so I've only now realized why the party is so quiet. I started with Beejive on my iPhone as an SMS alternative. It worked fairly well, though I ran into server disconnect and message delay problems. Then I started using it with Google Talk at work. There I ran into issues with messages going to one client or the other but not always both.
It wasn't until I started looking at multi-account desktop XP clients, however, that I realized how bad things were. That's where I found cr*pware bearing unwanted toolbars, neglected and buggy open source solutions, walled gardens from AOL and Microsoft, and web apps that want my google credentials (good luck with that).
Yee-uch. I know that smell!
So if IM is dead or dying, who held the knife?
I'm guessing it was a combination of Twitter, SMS/texting bundles, the mobile migration, the unflinching stupidity of Yahoo/AOL/Microsoft/Skype (basically everyone but Google), the non-multitasking iPhone and, above all, the complete absence of any plausible revenue stream .
IM, I barely knew ya.
 So why are there pretty-good IM clients on the iPhone? Hint.--
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