I'm using the Windows 8.1 developer preview for Windows Phone along with the latest version of tapatalk, and for the most part, it seems to be bug-free. The exceptions are disappearing lines of text and sometimes uploading inline pictures requires an extra attempt.

The only thing I can see that's constant is on posts where multiple pictures are uploaded. Some load, some don't. No biggie, but having to click each individual image is a pain.