The Expanded Text Ads are two times bigger than the current text ads, with a bigger headline and a long description. The characters limit are 30 for the headline and 80 for the description.
It is the biggest change to text ads on Adwords since it was launched 15 years ago,
Although the new Expanded Text Ads have more potential to have a better CTR (because they are bigger) and, consequently, a better Ad Ranking, Google is not giving priority to them. The old text ads are in the same competition-level with the Expanded Text Ads.