could not login with new launcher

when attempting to run the 0.7 launcher i was given the following error as a pop up and also on the console

Could not log in: java.lang.String cannot be cast to
net.minecraft.launcher.updater.VersionSyncInfo

if this is a connection error then that is strange because i had mojang.com open at the time

was the 14 of may at time of problem what ever java update was newest then