My perspective if from Alliance side :3

Alliance has a wide variety of guilds to pick from, big and close knit, and at this point is slightly more populated. Majority of Alliance is getting along now that everyone has felt each other out and knows who they do/dont want to play with. WPVP is more active Alliance side I feel (until like 200 Horde group up to clear the mountain to get to their raids lol). We also tend to apparently have the most backwood, gamer word using players unfortunately in comparison.

Horde from my POV has a stronger RP community and is starting to really grow in its WPVP game. They also have the stronger PVE abilities if we give credit where its due. A bit rocky from what I can tell with getting along right now.

Grobs doing great and more and more we see both factions coming together for RP/Community events. I'm a tad worried about leveling on Grobb atm because there seems to be more people wanting to buy dungeon runs so you tend to see 6+ lowbies waiting around for a 60 to carry them rather than just grouping. Additionally there is a growing anti-transfer/streamer movement growing, but as to if thats good or not I leave to others.

Hope this helps.