Differences in Belgium

I am moving to Belgium soon, and have been doing Rocket French to help prepare my language skills. I was wondering if anyone can tell me what, if any, differences there might be between what I am learning here about France and French culture and what I will encounter in Belgium. Cultural or linguistic differences. Mostly just curious.

On the French side of Belgium, I've only been in Brussels (but you can use French in the Flemish region and they understand you perfectly), but it's more laid back city than Paris (like the pace of the south of France, but not as sunny :) ). With respect to the lessons here, there's a lesson on idiomatic expressions (15.2) that I'm not sure extends to other Francophone countries.

The accent is a little different depending on the region, but for communicating in neutral French, the RF lessons are fine. It's more in understanding what is being said that you may need to train your ears a bit.

Here's a good example: https://www.youtube.com/watch?v=GBvSGZkN5R8

It's not universal, but I hear that "extended end vowel" a bit, and also the "ah" of an a sound that sounds more like "e(ng)h". You would probably hear this more outside of the big cities where there's less of a population flux and people are more apt to stay in the region where they grew up.

To add to the content here, one thing I have learned just recently is that Belgians tend to use the "better" words for seventy and ninety: septante and nonante instead of souixante-dix and quatre-vingt-dix