Gorgon Zee
Hero
Wasn't my experience with 4E at all, and I just wrapped up a 9 month campaign in August, so the memory is fresh.
I used a timer to track a round in combat: sometimes it took over an hour.
Regardless of the system, I like to use some sort of visual representation of combats and rarely do theatre of the mind.
yeah, some tables can play slow - but an hour per round is way slower than most. My experience is that an average combat took about an hour; faster at low levels, maybe up to 75 minutes at epic. I would say we both have anecdotal experience, but if you read the LFR adventures, they are pretty consistent with that -- expecting 3 combats at low levels, and more like 2 at higher levels. Assuming a 3.5 hour running time and typically about 2/3 of the time spent in combat, it's consistent with my experience.
D&D 4E combats are slow, because the game is all about the build and the tactics, but if your combats are routinely lasting over an hour, you may want to adjust your play style -- unless, of course, you like that pace!
I'd agree with you that OSR is much faster. At low levels, it's rare you have to make a decision, and a single roll of a handful of dice resolves it. Running AD&D at mid levels, a combat was 20 mins very often.