It's not that i'm a debian fan of which i am. Fedora, mandriva, opensuse, and ubuntu all follow the 6 month release (well i'm not sure about opensuse). And all release fairly close to one another. Because of this, they all use the same or similar versions of linux subsystems and utilities like the kernel, xorg, etc.
One bug that may be prominent in a version of mandriva may be the same bug you find in ubuntu because of nearly synced releases (different distributions with nearly synced releases have a lot in common). After that, you can have a release in 6 months, but a lot of it ends up half assed or just not as good as it could have been.
Since i like debian, i use mepis exclusively. On the other hand there's other awesome stuff out there like distros based on arch linux. And don't forget pclinuxos.
Pclinuxos and mepis are very similar in the fact that they center around the time necessary for something to be ready for release and stability with whatever necessary properly working backports at the same time. What makes pclinuxos and mepis different? Pclinuxos is rolling release while mepis is not (pclinuxos is rpm based while mepis is not, but i'm not getting at differences between packaging right now).
Among me hating ubuntu is that stuff like kubuntu and xubuntu used to be a labor of love and an awesome product, but they've fallen so behind so much, who cares, ubuntu should drop those projects (kubuntu has been plain, uninspiring, and had no innovation since the last lts release). Also, there comes distros based on ubuntu, which are equally as bad as normal ubuntu (linux mint 8 which is based on karmic koala was just as much a disaster as normal ubuntu karmic koala).
I got my reasons for championing awesome distros like mepis, pclinuxos, and arch.
I like stability and bug free software. In the mean time, i don't get along well at all with rolling release quite yet, and i definitely don't get along with the fact that rpm based distros don't have repositories as big as debians (compiling from source can get ugly and i dont like installing packages not from the repositories).