Everyone wants to kill email. I'm no fan of it either, but it does serve a purpose - a purpose that no other tool serves quite as well. Or more specifically, better than any SINGLE tool serves.
Take the article in from the Tech Nomad in Saturday's Boston Globe, E-mail: Drag it to the trash (with a different title online).
Michael Andor Brodeur describes many of the problems and issues that people have with email, and it is quite a list of problems: overload, scams, junk, distraction, leaks, hacks, fakes, viruses, poorly designed newsletters, coupons, lack of subtlety, etc., etc. Of course, one could respond to some of these specifically, but that would get long and boring and you have seen those recommendations before.
But the thing is, what is going to replace it? Broduer mentions a bunch of tools / services that have cropped up and that people use instead for some of the specific things that email does.
The problem from my perspective is that almost all the options described aren't globally available. Email sticks around because it just works. We can (fairly) reliably send a message to someone from any platform to any platform and expect it to get there. (Yes, I am aware that this wasn't always the case with email - in college we could only "email" within users of the same mainframe. I'm old.) What they do with it is a different story. But on most other environments, there isn't a consistency. This means not just one application but a bunch of applications running and lighting up in the background - that many more opportunities for overload and distraction and knowledge going off to die.
As usual, email - or any of the other tools we have - isn't the problem. It's how we use them to get things done. And we have many different things to get done...
Rather than grouse about your email situation, decide how you want to use it, and do that. Agree with your colleagues on which means of communication work best, and stick to that.