As others have noted, this a giant dry lake bed. There is tons of space, plenty of room to spread out and not be near other campers, which there are many on the weekends. The location is very convenient for accessing Joshua Tree and the surrounding areas. 

I was able to access the whole lake in my compact sedan. Just had to drive a little slowly at the entrance, where it is pretty rutted out, but not impassible. Easy to access in the dark too. 

Very reliable cell phone connection. Full service on Verizon LTE. I worked remotely during the week here.