If I launch a Joomla 3 site, will I be able to install extensions?

 
If I launch a Joomla 3 site, will I be able to install extensions?

Yes, you will be able to install extensions compatible with Joomla 3.x. The Joomla Extension Directory (JED) will have a 3.1 compatible icon to know which extensions are Joomla 3.x compatible; however, the best place to check is the developer’s site.