MD 2 won't be out any time soon, if you like to download 1.3, MDL site is down at moment ,but you can get it from here:
LINK Exit your messenger from system tray before installing.
If you use AVG antivirus, it prevents MDL to be installed, you need to disable it or use other antivirus. After installing, go to settings and disable MDL Today to not get advertising popups during logging into messenger.
/ 
