I’ve heard a few people wonder how Apple ported Webkit to Windows, so I cracked open depends.exe and took a look at what Safari was linking to. A few of the more interesting dependencies:

• Webkit (via CoreGraphics)
• CoreFoundation (and CF-Net)
• PThreads
• MSVCP8 (interesting to see them use MSVC SP2)
• SQLite3

So it’s not based on QT, and it doesn’t seem to match the iTunes set (which has no Core* dependencies). Looks a lot like a straight port of some of the base Cocoa libraries.