so after seeing a the last ep, as well as a re-run of the wedding ep where ted and robin break up i am not so sure about robin and barney ending up together.
in a nutshell, after ted and robin break up, future ted tells his kids that robin ends up travelling the world and living in japan and argentina (already happened), and a few other places (which haven't happened). so at some point robin must take off, dunno if that's before or after barney's wedding.
in other episodes: future ted i think mentions some other dude that robin had the hots for being part of the story down the track, so maybe she ends up with him. he also mentions how weird things got soon because (something along the lines of) not being able to be close buddies with exes and how awkward things got when referring to barney, robin and himself.
so maybe robin takes off and barney either gets back together with nora or someone completely different? maybe robin takes off before the wedding? i don't recall her in any of the barney wedding footage.