Last time I checked, arXiv was for pre-prints - the word suggests to me that it has to actually be going to get printed. It's not supposed to be a place to publish papers, just distribute them faster when they are being published elsewhere.
That's normally the case, but you do get some papers that just live on arXiv and never get published (either not submitted to a journal at all, or rejected).
It's always good to have several standard alternatives for distributing information, and it will be interesting to see what happens with this one. They could have chosen a better name, though - vixra sounds like something you'd see in a spam email...
On a en.wp note: I assume that arXiv counts as a (mostly) reliable site to reference? It will be interesting to see whether Vixra will also be, although I guess it'll be a case of each individual paper/ author set being taken on its own merits.
Mike