Started up the car today and it ran like crap...wouldn't idle, rough on slight acceleration, missing, etc. so I just shut it off...checked under the hood and everything seemed to be okay, but when I checked the carb "plugs" to make sure that I didn't have a vacuum leak, I noticed that one of the rubber vacuum plugs (Edelbrock 1407) was full of gas. What would cause this?

After I let it sit for about twenty minutes I tried it again and it started right up, great idle, no problems...but now I'm wondering if the carb has a problem just waiting to happen. Anyone?