I was there last weekend and it was very nice.
We were with the little one (almost 4 years old) so we did stuff that he could enjoy too.
Mainly a visit to the Zoo (which had a really cool aquarium part), lots of walking in the city, a torrent of bitterballen (a personnal favourite) and a trip in the spido (boat that shows you around).
This part of the aquarium gave me impossible and super expensive ideas for an ideal gameroom:
The "spido" boat tour, nice views, and most importantly: you can finally relax and enjoy a few beers:
It also gives you a view on the containers paradise, there's apparently room for 1000 units there.
How many are filled with cabs?
Thomas is this view some kind of wet dream for you?
And also I almost met André at the "Get Back café" where they have this groovy Q*bert wall:
We haven't seen much so we'll definitely have to come back, at least for a certain Star Wars cockpit that's sitting in a gameroom a few kilometers from Rotterdam.