I played Warframe pretty heavily back in the beta in 2013 for a few months but forgot about the game due to moving on to other titles. I saw it recently hit XBox Live and installed it and I was surprised at how far the game has come in development. (PC version is still a few patches ahead of the console version)
Anyway, played around a bit on the X1 version, and Destiny beta played a lot like this game only from a FPS perspective instead of TPS.
Warframe has more 'classes', more in-depth crafting and more missions/planets all updated regularly for free. Overall Warframe seems better than the small amount of Destiny I played in the beta.
Why didnt Warframe get the hype that Destiny does? Its it just because Bungie is a big budget hype machine and Warframe is an indie game?