By WA standards 3.7.2.1 to 3.8 is a huge jump in version numbers.
For reference, it took 30 publicly released beta patches and ~9 years to get from 3.6 to 3.7. In that time virtually every modern feature we now know and love was implemented - color maps, replays, wormkit support etc. Not sure if that is anything to go by, but I think this patch is certainly something to be excited about.
Any beta testing needed done I will volunteer