I've been playing Blizzard games since 1994 with Warcraft: Orcs & Humans and have bought every single title since.
I read every page of the manual(s) for Warcraft 1&2, Diablo, Starcraft, Diablo 2, Warcraft 3, etc. and have always enjoyed the storylines which were well written (at least up until Warcraft 3 but even Warcraft 3 wasn't poorly written, it just took a sharp turn for PG-13, which is okay)
You have brought us three amazing IPs and are one of the most influential figures in creating the Blizzard empire. You're also an amazing artist, and frankly are the father of the worlds we love.
But it is time to pass the torch to some different writers. The quality of writing - especially dialogue - has become really bad. It isn't your fault - one man can't be expected to churn out non-stop quality material for three different universes and one of those being an MMO with constant content additions.
You're currently surrounded by sycophants because you're a big wig at Blizzard and nobody wants to get in a political battle - so please, listen to us fans on this one, or better yet - take a look at the cinematics and dialogue from Diablo 2 (especially the one with Baal) and compare them to what we have now.