Sure a few reasons;
OpenSUSE has one of the best KDE4 setups. They've done a lot of work into making KDE4 really shine. The Firefox KDE integration is AWESOME, and not something I am sure the other distros are shipping with. There is also additional work above and beyond stock on OpenOffice and such. A great attention to detail on the theming (not that you can't change that on Ubuntu and Fedora).
Zypper is hands down the best RPM tool and I would say on par or superior to Apt. Definitely a step over yum.
Nomad provide an RDP server for Linux that supports Compiz, not sure if that's been ported to other distros.
iFolder (if you care about that) is so far only packaged for SUSE, I believe.
Also Yast is great to administer your system if you're not command line friendly. It used to be atrocious, but now is very much decent. I still don't use it that much, but it has an appeal to people (especially our Windows friends). Overall it's a solid distro and I would say on par with Ubuntu and others.