I'm having problem also, started this morning
So, i deleted tek folder and ran launcher again, this is what happened:
Error downloading file for the following pack: Tekkit
Failed to download http://mirror.technicpack.net/Technic/mods/qcraft-v1.0.1.zip
Please consult the modpack author
I tried to download launcher from site and would not connect to download site
and ideas? Thanks
Edit 1 Ok, I deleted tek folder again and started old launcher, again it hung. So, i hit play again as login was auto. it hung again, hit play again, then it loaded. Took a while but problem (whatever it was) seems fixed for now.