Haven't had that experience myself but it sounds adorable.

I'd love to see some photos of it, or even a video, I bet they look really cute.

Edit; Actually after watching that video that was posted I realised that Taggart did use to do something similar to Leo. It wasn't so much kissing though but more "bopping" the head and trying to sniff the ears. Maybe there is something about the smell of cat ears that some dogs just really really like ?