Hi Braden -- it's great for a day anchorage and some people have been placing moorings, but there is still plenty of room. It's not a great overnight anchorage unless the weather is very settled, as it's not very sheltered, and on summer weekends it gets crowded during the days with picnicking boats and raft-ups.
The better anchorage in the Greenwich Islands is either north or south of the bar connecting Big Brother and Little Brother Islands. North of the bar is a little deeper and moorings have been placed there, but there's still plenty of room. Don't cross the bar except at extreme high tide, as the bar dries out at MLW. Tidal range averages about 7-8 feet. Watch the charts carefully -- the boulders are really there even and don't move.
Shoot me an email if coming to Western LIS. Would be a pleasure to meet you.