Not all the fingers are no-wake zones... There are a couple awesome ones that open up and are great for day camping...
It can be pretty busy during the summer. Best time to get there is either Sunday or Monday morning and camp during the week. The weekends can be hectic at times.
Campgrounds nearest the lake (Pine Knoll Campground) area all first come first serve, and where you want to be. There are cabins and permanent travel trailers available for rent also in the same camp ground. When the water level is low there is a bunch of dirt over flow camping available also. But when the lake is low, the shore gets steep and there aren't many good places to hang out lake side unless you find one down the lake that would only be accessible by watercraft of some sort.
All camp sites in Pine Knoll are dry sites, if you want hook ups you have to go up the road (which is up hill), so to get to the lake you're either hoofing it, or driving a vehicle. That being said, I've only ever stayed in Pine Knoll the 30+ times I've camped there.
It can be pretty dang hot in July and the water temperature fluctuates with weather conditions. It can also get windy in the late afternoon which can cool things down, but obviously makes for a choppy lake.
In my experience there aren't a ton of bugs, but still bring your bug spray and candles.
$6/day to ride on the lake per watercraft. There is a pretty large no wake zone to get through to get to the main part of the lake.
Very kid friendly, and you can get hardcore on the riding as long as you keep out of other people's way.
There is a pretty great camp store and attached restaurant that serves meals until the early evening. Great for when you're hung over and don't feel like cooking yourself.
Free wi-fi internet connection.
Basketball, volleyball, and horseshoes.
Quiet hours are strangely enforced. I've been there when rangers are strict and I've been there when generators and music doesn't stop all night long.
Call ahead to see what the gasoline situation is like. The last couple years it has been very on and off whether they have any for sale at the lake or not. Paso Robles is about a 20 minute drive to get gas and other provisions.
Dump station has been remodeled and are very nice for what they are.
Overall it is my favorite place to camp whether it be tent or motor home camping.
http://www.nacimientoresort.com/marina/camping.html
http://www.nacimientoresort.com/images/site/campground/campgrounds_map.jpg