>Consider the plight of Windows users. They don't have the option of switching to KDE of XFCE, etc.
Windows 7 is supported until 2020. That means it will have been possible for a Windows user to use the same basic UI paradigm without significant interruption - but *with* incremental improvement - for *25 years*.
Twenty. Five. Years.
None of those projects has even *existed* for that long. Do you think Gnome 3 will still be around in 2020? Anything's possible, but let's say I'd be mightily surprised.