That's a valid point for a small team. There's not a lot of friction for them to add an additional chat tool on top of what they already use. I'm guessing that

That's a valid point for a small team. There's not a lot of friction for them to add an additional chat tool on top of what they already use. I'm guessing that most people's Skype contact list is like mind: various present and former coworkers, family, friends, and so on. These additional contacts beyond the small team are what makes it hard to replace Skype. Everyone's already using a perfectly functional chat tool, so it comes down to whether push-to-chat is that compelling of a feature that you'd pay for it. Also in terms of a general consumer app vs. a team-based app, perhaps the terminology can reflect this? Instead of a contact being a "buddy" (which doesn't sound professional) what about just calling them "Contacts" and the ones you want to be able to insta-chat with you can be marked as Trusted?