All Mint point releases (17, 17.1, 17.2) are going to use Ubuntu 14.04 as a base. That means upgrading Mint 17 is low risk task until Mint 18 is released in 2016 (based on Ubuntu 16.04).

Also expect Mint Debian Edition based on Debian 8.0 (Jessie) to be released later this year. Currently the Debian edition of Mint is rolling release but the developers have agreed that starting with Jessie, they will use only stable releases to base their version on.