I have the same issue. Or rather, before the update my iMac would not connect to nor display my home wi-fi network. I attributed the issue to sleep (as I very rarely shut down my computer) and could fix it following the manual steps (that is, removing my home network from the preferred networks list, rebooting and reconnecting).
I thought that the update 10.9.4 would fix this exact behaviour, but it seems that it does not do so. I installed the update July 27 and have had to follow the manual steps to reconnect twice. Not a big issue for me, but annoyingly bigger to the missus.
Yours etc.
Eggs