Google has recently updated the link schemes webmaster guidelines warning against optimized anchor text, advertorials, and guest posts. As per the new guidelines, Google has clarified that links with optimized anchor text in press release will be regarded as unnatural links.
In a video hangout discussion with Search Engine Land, John Mueller, Google Webmaster Trends Analyst has revealed more things about the new link schemes documentation change. Equating the press release to advertisement, John said that it is alright to have direct URLs passed within the press release that is followed. However, in order to be safe, John recommends nofollowing of even those links (specifically the links, which are not optimized anchor text).
He pointed out that press release adds a great value to a company. It is all about getting a word about the new product or service launched to the press. If the press hears about the new product or service and decides to write about it on the website, the links passed do not have to be nofollowed. John said that Google gives most value to the links passed through news stories written editorially.Google Wants Links in the Press Release to Use Nofollow Like the Paid Links!,