EOS is a decentralized application development platform that attempts to solve many of the problems that prevent programmers from using competitor Ethereum. The developers promise to be an improved version of their competition. The EOS blockchain offers pillars for developers to adopt the network as the main platform for dApps.
Whether EOS will actually overthrow Ethereum only time will tell, but there is no doubt that Dan Larimer is an extremely competent person and has a lot of experience to create something really innovative and with a processing capacity far superior to competitors.