Honestly, with Strawberry Perl, the only reason to install Cygwin is if you're needing it for something else anyway. Strawberry provides a good Perl, CPAN, and gcc environment for Windows that just works. There might be a few problem modules here and there, but the situation is much better than ActiveState's perl and takes much less space than Cygwin.

Also, with most machines readily having the CPU speed and memory to handle a virtual hardware machine or hypervisor, the best solution for Windows and a Unix on the same box turns out for many people to actually be Windows and a Unix running on the same box together. That means if I need good Unix-like behavior but can't give up Windows, I'm likely to set up a Windows VM on top of Linux or OS X. Some will do the opposite. Cygwin and Wine still have their place, but they are not as important as they once were.