Watched EP 22 of the 4th season regardless of the time being 4 am and I didn't yawn a single time during the finale. While trying to not spoil it, I will simply say that it worked out like a lot of people thought it would. It also had a cliche timeskip in the end to show how the lives of all the protagonists is progressing.
I think that I was in a way a minority, in the sense that I really liked the whole series. I also feel that ending the series with 1 season would have left either plenty of plot holes in, or would have simply been less fun. Lots of people curse the series for going further, but if they would have wanted to tie everything together in a single season, it would have been a different show.
The 3rd season was admittedly quite weak, though given the circumstances, it was good enough to keep me watching, unlike some other shows (hello Lost). I'm just really really glad that they didn't introduce some freaked up plot twist to drag the series unto a 5th season. All good things must come to an end and I'm glad this end came before I was tired of the show.