I've stuck with openSuSE/SuSE since the early days, and doing Tumbleweed since about when it surfaced. There are several reasons I didn't switch over to Ubuntu (and a few reasons I wanted to, but the pros outweigh the downsides for me).
1. Active Directory: I'm not a Unix shop and everywhere I've had a need for it, AD has been the predominant identity service in the environment. Getting openSuSE setup, via yast, to work with my AD account is really simple. It can be done everywhere else, too, but being able to set it up during installation without touching a config file is nice.
2. Bleeding edge: I like to play and Tumbleweed was always on a later kernel (and other core bits) than other distributions, giving me access to the new toys early on with the "feeling" that I'm not running "beta" (and feelings aside, I've not run into anything on the stability, yet). Never having to think about doing a "distribution upgrade" (because you're basically doing it in pieces every time you update) is nice, too.
3. YaST: Much like the easy AD integration, there's a whole mess of administrative things that can be done without editing configuration files or using console tools that I'm not in nearly enough to memorize their usage. Simple things like opening a port in the firewall are as easy as they are on a consumer router and the ncurses interface is perfect over an SSH connection (I haven't used GUI YaST but it looks nice, too). People always say Ubuntu is the most "n00b" friendly Linux distribution, and it probably is when the large community behind it is factored in, but I find SuSE to be superior, personally.
On the downside, though:
There's less available in Zypper. I get jealous when every answer in StackExchange includes an apt-get and about 15% of the time no package even exists for whatever it is that I'm being told to apt-get. But it's little more pleasant to watch on the console.
The smaller community makes StackExchange less useful and they use different tools. Much of it is due to the bleeding edge nature of Tumbleweed and I've read plenty of "it's better, that old stuff will be deprecated everywhere else, too" and I can't speak to the merits of any of that, but when my network connection goes south, I instinctively reach for "ifconfig" and it's not there. And all of the help out there points me at things that don't work, either[1]. And because it's a rolling distribution, these kinds of changes don't pop up when you expect them (like when you're doing a distribution upgrade...)
Tumbleweed's rolling update model has thoroughly broken on me, once, but not in a "hey, it just decided not to boot this time" kind of way. I believe this happened when they switched to "Leap" and "Tumbleweed" as the only options. I thought I was up-to-date, but I was pointing to repos that were invalid and had to modify my configs and download an .rpm to fix it. Other than not seeing software updates (which is pretty odd since there's usually something every time I update), there was no indication that anything was wrong.
Out of the box, sudo isn't setup (maybe it is, now, I haven't done a fresh install in a long time). It's not hard to get working, though.
[1] It's one of the new "ip something" commands I can never remember when I need it: http://www.linuxfoundation.org/collaborate/workgroups/networ...