I've seen a couple threads that mention these sights will fit on the shield but I haven't seen anything on how the POA/POI changes with these sights. Any info would be appreciated.

I would be interested in the answer as well...

I emailed trijicon and this was the response...

Good Morning

Thank you for your interest in Trijicon products. We are in the process of verifying the optimum configuration for this new and heavily demanded pistol. Keep checking our website for new products/information as it comes online.

got a similar response from Truglo about the TFO's. everyone seems to be putting the standard M&P TFO's on the shield, truglo isn't willing to say that's a good idea yet.