Ads always annoy me, especially when they get in the way of what you're doing. If they were unobtrusive I would just let them be, but they always progress to more and more annoying to gain attention. Skype Ads are no different.
First there were none, now there are some. And now they change colours, blink on and off, and remove focus from the message window in the middle of typing. They make a workable program frustrating to the point of looking for an alternative. Let's not even get into the ridiculous memory usage of the program.