Here's the biggest issue we ran into, which I'm not sure WhereBerry has solved either:
Let's say Julie wants to see Fast Five (ugh), and she wants to know which of her friends would like to attend. At first, she considers using WhereBerry, as it's designed for such things. But wait, Julie's friend Joe doesn't have an iPhone. And I know her other friend Steve doesn't use social networking sites besides Facebook. Julie resolves to just send an email out to everyone, so she knows she'll get a response from everyone she wants to talk to in one step. Plus, she already has everyone's email address.
See the problem? Julie is forced to isolate her non-WhereBerry friends, or invite some on WhereBerry, and others via email (huge inconvenience). This isn't solving the problem. It's compounding it. Let's say WhereBerry tries to "solve" this problem by allowing Julie to invite non-members via email. We tried that, too. While it sounds good on paper, nobody wants to send their friends an email saying "Hey I want to go to this movie. Join WhereBerry to tell me your response!" In reality, they'll probably text Julie saying "Sure, I can go! Why didn't you just text me?"
It doesn't matter if 95% of your friends are signed up to WhereBerry. You'd need 100% to get people to use it in any consistent form.
It's not a tough problem to discover, as many products have attempted to solve it. But, no company has succeeded, specifically because of the scenario posed above. I wish WhereBerry luck, but I think it needs to solve the problem before being a "cool plan-making utility." There are millions of those.