WINE is definetely not an emulator. Neither a runtime. Wine is an implementation of the Windows 3.x and Win32 APIs on top of X and Unix featuring a Windows compatibility layer. Wine provides both a development toolkit (Winelib) for porting Windows sources to Unix and a program loader, allowing unmodified Windows 3.1/95/NT binaries to run under Intel Unixes (some screenshots
here). Wine does not require Microsoft Windows, as it is a completely alternative implementation consisting of 100% open source Microsoft-free code, but it can optionally use native system DLLs if they are available. WINE's project leader and
CodeWeavers' software engineer (a company which sells a modified WINE version), Alexandre Julliard, answers a series of questions to OSNews regarding the project and its future.
Well, I got my answer on having an independent GUI. I guess it comes down to their philosophy of coexistence with the X framework on the native OS which pretty much implies it's got to be Unix. I wonder how many Wine ports have been done to non-unix platforms? I don't fully buy the line that the unix stuff is confined to a small section. If the X dependence is included, I suspect the unix dependence would be much stronger. P