If there was one single thing that I had to say was vastly improved from previous generation BlackBerry smartphones it's certainly the browser. The BlackBerry 10 browser is awesome for everyday usage and for some, it's the best 'app' on a BlackBerry 10 device period. That's not to say it's perfect but it works amazingly well and I don't really have any huge problems with it.
If you're looking to test the browser out for yourself and have a bit of fun, then you should check out the Google Chrome Experiments website. Never heard of it? Well, it's a website set up by Google to, in a way, push browser limits and showcase what is possible or as they put it:
Chrome Experiments is a showcase for creative web experiments, the vast majority of which are built with the latest open technologies, including HTML5, Canvas, SVG, and WebGL. All of them were made and submitted by talented artists and programmers from around the world.
The cool part is that there is some games and demos on there that work on the BlackBerry 10 browser thanks to its support for all of the above mentioned coding. Personally, I've become quite fond of playing Run Pixie Run which is sort of like Jet Pack Joyride only it's been built on Pixi.js. Go ahead and check the experiments out, some of them are really cool and show off the BlackBerry 10 browser capabilities quite well.