If you're not already doing this, the easiest way to release it is to push down on the back end with your thumb while pulling up on the front with your index finger.
It is easier by doing that, but still kind of difficult to release. Union has actually added a release lever to the toe ratchets on most of next season's bindings.
The higher-end ones will still not have one, but they will have a new release mechanism to make it easier.
Hope that helps.