@Flanker2
Indeed, I posted about it after landing in JFK. Here's the topic
viewtopic.php?f=4&t=49545 So both ways there were "issues"

I wonder if it was the same aircraft?
Yes, I would still fly SN. I hope that these issues are glitches that will be fixed soon, and I wish our national carrier lots of success. Bu then let's see how they deal with my complaint. I hope SN's management realizes that beyond all the marketing, what matters most to customers is their overall experience with the company, from the moment of ticketing to dealing with any issues after the flight, and that a disappointed/unhappy customer will not only refrain from flying with the company again, but will also share his experiences with all his friends and colleagues.
@Inquirer
Of course none of what happened was dramatic. But then, I tend to hold companies with whom I do business to high standards and I expect everything to go smoothly. If all customers were to make contingency/backup plans and decided that nothing is a big deal, that they''ll just sort it out later, then nothing will ever improve I'm afraid.
UPDATE 20.01.2013
After 2 e-mails to Brussels Airlines' Customer Relations, contacting their Call Centre, and filling the form recommended by Kim/Inapa above (thank you!), I finally received an e-mail reply after 5 days saying "We will investigate your claim and have made up a file in your name. Kindly be advised that, at the moment, the handling of a claim can take up to five weeks." Yes, that's
five weeks
Will keep all of you posted on how this gets resolved.