SSPVP3 is mostly improvements and recodes to sections of code, along with adding support for 3.0.x features.
Herald yells inside Alterac Valley are changed to be more consistant and will be colored by the faction that triggered it, you can also see how many resources are gained via the Mines inside the overlay along with chat alerts when the Captains are slain by a faction. Timers for how long until graveyards, bunkers and towers are included for Arathi Basin and Alterac Valley.
Includes match information like time left, nodes to win, final scores for Arathi Basin and Eye of the Storm. Along with flag carriers inside Warsong Gulch and Eye of the Storm, including coloring by flag carrier class and carriers health (when available). Other features are things like modifying the players arena panel to show both weekly and seasonal stats instead of having to toggle them as well as displaying team leader even if they're offline, or showing break down by server/class on the battlefield scoreboard and more, see configuration for a better list on all the features SSPVP3 has.
See, /sspvp ui for configuration, /arena for different data functions like games required to hit 30%, points -> rating or rating -> points conversions.
Thanks Narvinye on Die Argustwacht (EU) for German localization.