I'm not going to embed the adds. If you haven't seen them, they can be found here.
Scientology was started back in the 1950's by hack science fiction writer L. Ron Hubbard. In my opinion, Hubbard never could write his way out of a wet paper bag. I read Battlefield Earth when I was in high school, and I'd love to have those hours back. It was painful. And the doctrines and beliefs of Scientology also read like painfully bad science fiction.
For instance, Earth, which is actually the planet Teegeeack, was set up some 75 million years ago as an interstellar prison by Xenu, the Evil Galactic Overlord (not to be confused with Xena, Warrior Princess.) (Want to do something fun? Google "evil galactic overlord" and count how many hits are related to Scientology!) According to Scientology, we are all still prisoners of Xenu, doomed to endless reincarnation, until we realize that we are really god-like galactic beings, called "Thetans." Sad that people buy into this stuff.
It is well known that Scientology deliberately targets prominent people, such as actors like John Travolta and Tom Cruise. Founder Hubbard desired to use such "Opinion Leaders" as "Social Proof" for Scientology. (Read an ex-Scientologist's description of the recruitment process here.) These prominent people become the celebrity spokesmen of the cult.
Scientology is also very harsh against critics. In 1994, The Washington Post published this article, detailing many of Scientology's tactics for silencing opposition. This is a long expose, but well worth the reading.
This is a scary group, secretive and with their own quasi-military arm, the Sea Organization. Scientology has been repeatedly exposed as an abusive, manipulative group. Their website (follow link at your own risk) claims that they are undergoing huge growth, but their innate secrecy makes that hard to confirm.
In addition to their new ad campaign, Scientology has been very much in the news lately, with an expose series in the St. Petersburg Times, and fraud charges against the "church" in France. There have long been efforts to ban Scientology in Germany, where it is not recognized as a religion, but as a "commercial entity."
Scientology is just more evidence that, once someone rejects the truth of God and the Bible (see Romans 1:28), the only question left is, "Which lie will they believe?"