Yeah, this has been discussed countless times over the past few days since the update was released. Adobe has acknowledged the error. It IS an error. It is a mistake. The solution is to choose the option to open anyway and check the box to not show again and wait for the next update when the error will be corrected. In the meantime, you can work as usual and your roundtrips from Lightroom to Photoshop will function as they should. It's just the message that is in error.
Thanks, I had this problem too!