How to wait until element's text had changed in WebdriverJS?

I've found in Alister Scott's blog how to wait until element had changed to specific value. But I can't solve problem with how to create waiting for element to wait until its text had changed FROM specific value (in my case from '-') to anything else (in my case it's a counter, so I can't set specific value to wait for).

Any ideas?

Thans in advance!