The specific line in the link schemes document is:
Links with optimized anchor text in articles or press releases distributed on other sites.
John Mueller, one of Google’s lead Webmaster Trends Analyst, was kind
enough to answer some of my questions around this documentation change
in a video hangout. The
questions from SEOs and myself around the new link schemes documentation
change are in the first ten minutes, the outcome was to nofollow links
within press releases.
Throughout the video, John Mueller equated press releases to
advertisements. It was specifically asked if all links in press releases
need to be nofollowed or just “links with optimized anchor text” in
press releases need to be nofollowed. While John said it would be
somewhat okay to have direct URLs linked within press releases that are
followed, he did say to be safe, he’d recommend nofollowing even those
links (i.e. the links that are not even optimized anchor text).
Google’s John Mueller did add that there is still great value to using
press releases. The goal of the press release is to get the word out to
the press about your new service or product. When the press hears about
what you have to offer and if/when they decide to write about it on
their own sites, those links do not need to be nofollowed. In fact,
those stories written editorially are the links that Google values the
most.
Google’s Matt Cutts has said that links within press releases do not pass value. Although SEOs have proof
that this is not true, it does seem that Google is taking even more
direct action against abuse of links within articles and press releases
that are paid.