I'm OK with a unobtrusive banner ad. I hate forced ads that get in the way of my flow (whether it's gaming or reading or work). I hate forced ads that can't be skipped.

I understand the reason for these (they often have an IAP that will remove ads, so the more annoying the ads the more likely folks will be tempted to buy it). But doesn't make it ok. I usually just leave a one star review and uninstall.