The issue is: as it stands now, ONLY people in a full group (so 10 for WSG, 15 for AB, etc) will be allowed to partake in the rated bg's.
This means you'll have to form a premade first.
You can PuG it when the rated bg is announced, or you can have a guild that makes premades...
But either way: without a full group, you're not getting rated bg's.
This has several consequences:
First: pvp guilds will dominate these rated bg's very soon, I fear.
second: you will NOT get an invite into a 'pugged' premade (sounds contradictory but it isn't) if your gear and achievements are not the best pvp can offer...
Third: if you do get in a group, you will get steamrolled by the first and second...
And since you ONLY get ratings for winning (so NOT objectives), you likely get next to nothing.
Imagine wsg rated bg:
PvP guild zerg first flag, than camp your gy...
Good luck countering that, we're not talking some scrubs here. It's a gladiator team in relentless gear working as one.
Another issue: what if you DO make a regular premade/
week 1 AB: 15 people needed
week 2 wsg: what 5 people are not getting their ratings this week?
Go go, make a premade rota...