I'm pretty sure we only get 90% of Act I and whatever happens at Moonrise Tower will be the conclusion to the act.
Oh, I highly doubt we have ''90%'' of act 1 done. After all, there 3 routes to the Moonrise Towers. One is that mountain pass, another is supposed to be a path through some forest/swamp? So maybe we've got like 60% of the act 1 actually available. That's of course assuming that the other 2 ways of reaching the towers are as large as the Underdark is.
And I dunno about you, but finishing everything we have currently available to us (basically having meta knowledge of what's where and such) took me 45h. My first run took me 70h, and on my 2nd run I discovered I accidentally skipped some things. Now I wonder how long it would take me to do everything on a 3rd run? But so far I'm waiting until we get some sort of patch/hotfixes to go through all of that again.
