Sounds like you are proceeding with caution, and tapping into the wisdom of a good poly forum, which is exactly what you need to do. Just take it slow, and check with your wife frequently to see how she's feeling about things.
Curious: Is she also interested in dating new people, or is this just mainly her giving you the okay for it?
Regardless of whether you decide you're poly, I hope you and your wife enjoy much happiness together.
Love means never having to say, "Put down that meat cleaver!"