Only on start up, though. I've tried deleting old networks, making sure wifi is at the top of the list, but I still have to wait something like 30 secs before I can go online. I'm running the latest 10.10.2 public beta, because I was hoping it might fix it. It's been happening since 10.10.0. What with that and the beachballs when there's a confirmation dialogue (since pre release 10.10), I just don't know what's going on with OS X these days. They get it right just in time for a whole new release to come out and it all starts again... Two year cycle, anyone?