Victoria can't be the mother. 2030 Ted mentioned in a previous episode that the mother plays the bass guitar; have we seen Victoria do that/know that she does? Certainly its possible that she already does and we haven't seen it, or that she eventually learns, but I don't think Victoria's going to be around for long.
My guess: Ted meets the Mother at Barney and Robin's wedding (where the Mother was one of the musicians in the band playing and Ted runs in to her again after the wedding, while waiting for the train in Farhampton in the rain.
I get why some people are over the show, but I still love it and will continue to watch till the end.
: If you google "How I Met Your Mother Season 7" -- there's a site called Project Free TV that streams all the episodes there. That's how I was able to get all caught up last week. Granted, some eps the resolution is less than stellar, but not terribly so.