I talked this over with another blogger. I do not like to be an alarmist, but beware. I have been reading blogs for several years and this has happened twice to me.
I roll my cursor over a sidebar ad campaign on some of the blogs and I them have all these pop up sites showing up on my computer. I know some use them to generate money to support you sites, but it has caused trouble for me.
I deleted these add ons caused me to delete them 6-7 times over the course of the day. Once deleted it prompts them to re-install. Very Frustrated. I would hope the Ads you subscribe to are reputable and not just sneaky creepers.
I'm sorry but I think I will rethink reading blogs I like to read to stop this action from going on. Hopefully you understand .
So this is my experience so it maybe isn't yours. I thought if I talked about it maybe it would explain to others when they first started having trouble. Chris