This is the start of an arms race. I expect by the time this launches there will be tools provided by the ad-networks to detect blockers and allow the content provider to block access.
Exactly - that will hurt the UX like nothing else ever has. If people find out web sites don't work on their phone or tablet - the dumping of that platform to the competitor will be rather quick. Partly why Windows Phone didn't fly was IE - the websites looked crap compared to WebKit based browsers. Microsoft had to do unprecedented stuff like emulating WebKit to get over it.
They will only break if people have manually installed an ad blocker. I imagine this will be the vast minority of users, but will give the content owners and ad networks a reason to think about what they are doing to the UX of their website.
