I just finished the game 5 minutes ago. I've been playing it non stop for 15 hours now. Note that I blasted through the game simply to experience the storyline, the actual gameplay had I took my time would be considerably longer.
Anyway, about the cutscenes, the ending was over an hour, possibly 70-75 minutes. The second longest cutscene is the 40-50 or so minute one I mentioned mid game. The second half of the game is extremely cutscene heavy with at times very short bursts of gameplay so if I did disregard some of the short intermission gameplay sequences I may arrive at 2 roughly one hour long sequences, but not anywhere near 90 minutes. I didn't use a stopwatch though.
I can't honestly give any impressions as of yet. The ending in particular is something very unexpected and I will have to sit on it for a while contemplating everything. Will need to replay it again more fully to be able to write a well founded review. But yeah, no single 90 minute cutscene. Bummer! 
