(Can we count Feral Pigeon?!)
Yes, we can count Feral Pigeon, as long as the local population is self-sustaining, even if local birding rules don't allow non-native species.
Meanwhile, scanning my final list for the day I can add one more for the UK:
Red Kite
We'll be assembling at least lists for the USA, the UK and Europe excluding the UK, based on inputs so far. Technically we have an Australian list too, but we've only had one post so far, so the list doesn't need much compiling. Come on Aussies, were are you?