I'm midway though watching Fringe season three on DVD. So far the story has been really entertaining. The relationships between each of the characters are developing more each episode, which I like. There's nothing more boring than a tv show in which all of the characters remain unchanged. Especially a show with universe changing plots. It's unrealistic and sci fi shows need the characters to be realistic so that the fantastical elements seem possible.
The ongoing story is building momentum. I can only hope it's leading to a satisfactory ending but I won't know till I watch more seasons. There seems to be a lots of plot threads that need to be resolved before the ending.
The show is very engaging. I keep wanting to watch episode after episode, which is good. I recommend the show to everyone, whether you like sci fi's or not. However, start from the very beginning as the story can be a bit convoluted.
I give Fringe 8 universes out of 10.