Yes it is, but I wouldn't recommend it. If you have the option, try to run a clean installation. Especially if you have a lot of non-SUSE software installed, this may not run anymore after the update. The larger the step in version, the less I would recommend an update. Very often the structure of configuration files changes and you may lose performance. My advice: keep your data (/home) on a separate partition. This will allow a fresh installation in which you can keep your data.
And as a general rule: Never change a healthy system! I see no reason to abandon a perfectly well configured system every few months when a new version is released.