In case anyone want to know:
Safari 5 (Windows edition) works great with WINE in Ubuntu 10.04 (32-bit, I don't know about 64-bit). My WINE installation also has .NET 1.1, but I don't think Safari relies on it. I haven't tried streaming media or Flash, just the essential browser capabilities. It is smoooooth.
Why? I have some XML with XSL files created in Windows, and it seems that Firefox does not interpret them as desired (this is a known feature, or bug, in Firefox on any platform). But Safari does it.
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