I'm just as frustrated Barney. Also, vague spoilers ahead, but spoilers nonetheless.
I think How I Met Your Mother is pulling an anti-Lost. You see, after a few seasons of build up Lost said, “Ok, we’re going to end this after six seasons and wrap everything up.” They had a nice timeline set for them where they could explain everything. Whether they succeeded or not is up to you. On the other hand, HIMYM says, “Let’s keep adding stuff and keep going and never ever get to meet the mother! Oh kids, turns out your mother was in that coffee shop with me!”
HIMYM, I love you, but you better have one hell of a payoff in mind.
So for a while we’ve known that Ted meets the mother at this wedding. We don’t know whose wedding it is, but we know that he’s the best man. Now we’ve learned that we’ll learn whose wedding it is at the end of this season (season six) but that point in time will still be off in the future from the “present” time of the series. Season seven will go back to “present” time and focus on how that couple will get hitched, even though they might not get married by the end of season seven either. Basically it’s a whole other plot point for us to get our heads wrapped around before we learn who the mother is and an excuse for the writers to justify the show being renewed for two seasons.
I would say I’m angry at them for withholding the mother from us, but I don’t want HIMYM to end so quickly! I actually rather enjoy the episodes that have nothing to do with Ted dating someone and this means more Marshall, Lily, Barney, and Robin stories! Woo! The one thing I think this really depends on however, is who is getting hitched at the wedding. Leading the pack right now are Robin and Barney, which would be interesting but we have no way of knowing if it's for sure. It could just be Robin or Barney or Ted’s high school friend (though I HIGHLY doubt that). I’m a little surprised at this move, but I’ll wait until the end of this season to see if it’s worth it. HIMYM has made a lot of promises and so far, they’ve kept them all. Let’s see if they can keep it up.