I don't know how many Linux users there are out there, but I figured I would post this information here irregardless. I have been frustrated for a long time about the lack of good tagging utilities under Linux (especially ones that support id3v2.4/UTF-8 encoding), so I was happy when I found this program that not only a) is free of charge, and has great functionality and is in constant development.
Ok, all gushing aside, here is my configuration that allows me to run Mp3tag v2.35n (yes, the current dev. version) perfectly:
Distro: Gentoo (not that it matters)
Wine version: 0.9.12
Note that my Wine install has been configured using Winetools
The install goes perfectly. When first starting Mp3tag, it will complain about the lack of gdiplus.dll. You need to copy this file from a real Windows installation (should be able to find it in \Windows\system32). After I copied this file over, it started up quickly, and runs perfectly.
Here is a screenshot: