Gent was the largest city in the Low Countries in the late Middle Ages, it was even bigger than London or Cologne. It has preserved its medieval treasures and core well, though as a prospect WHS it is hindered by nearby Brugge that has been on the List since 2000. Ánd Gent already has two WHS within its borders: like so many historic Flemish towns, it features both a designated Beguinage and Belfry.
I visited Gent on a day trip from my home - it's about a 2 hour drive from the center of the Netherlands. My main goal was to see the 'Lam Gods' (Adoration of the Mystic Lamb), the famous altarpiece painted by the brothers Van Eyck in the 1430s. This precious piece of art is displayed at Saint Bavo Cathedral, the place it was designed for. Although it is very much connected to the history of Gent, I doubt it will be seen as 'immoveable' - so a future WH nomination can not be build on it (it isn't named either in the T-List description).
The rest of the city center is full of churches and pretty old guild houses. It's pretty touristy as well, besides daytripping Dutch individuals, I met groups of Germans, French and Italians. It is also a 'normal' city, with a lot of students and bikes and trams that ply the streets. I found it a very pleasant destination for a day out (great cafees and restaurants too), but doubt that it has enough distinction to set it apart from other cities in the region.