Well 13.1 is going to be supported until the end of 2016, which is fairly long-term. You probably don't want to continue using a distribution that is much older than that. But it is true that SuSE doesn't follow the Ubuntu model of supported and ephemeral releases; they all last a reasonable time.
Looking at various forums, it seems that OpenSUSE does not have LTS version
http://www.linuxquestions.org/questions/suse-novell-60/opensuse-lack-of-lts-4175462401/
Well 13.1 is going to be supported until the end of 2016, which is fairly long-term. You probably don't want to continue using a distribution that is much older than that. But it is true that SuSE doesn't follow the Ubuntu model of supported and ephemeral releases; they all last a reasonable time.