my wifi connection keeps dropping every 10-15 seconds during some parts of my day, I brought it into Apple this week, the genius reset some network settings and I'm still getting the same issues. It's only my rMBP (late 2013/8gb/256gb) that's getting this issue, all my other apple devices never drop any connections. I recently upgraded to comcast's 50mbps connection, also, my router is built into my comcast modem.
EDIT: wow, after some googling, I found out that it was due to having my bluetooth on that my wifi connection disconnects frequently!! omg, I'm going to set up another genius bar appointment. That is unacceptable that I can't use my bluetooth speaker without having constant wifi connection drops!