Which advantages as well as disadvantages do geoTLDs like eg. .berlin have?

A geographic top-level-domain, also called a geoTLD, should have a clear focus on a geographic-, geopolitic-, ethnic-, language-, or cultural-collective. Due to this, it would be possible to use these new, so-called geoTLDs to match a domain,or the content and the website’s users, to a regional and/or local searchmarket.

This is already the case for country-code top-level-domains, called ccTLD: Google considers local top-level-domains to be strong GEO-targeting signals, in their algorithm. By using a ccTLD (country-code top-level-domain, like .de, .ch, .at, and so on) Google is made aware that the website is focused on a specific country and made specifically for an audience within this country.

How does Google evaluate geoTLDs?

geoTLDs may gain a certain degree of influence, if they are used by enough people for Google to collect reliable data, and Google has learned how to deal with these new domain endings.

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Video explanation by Matt Cutts on this Topic

How will Google treat new TLDs?

How will Google treat the new TLDs where any top-level-domain is possible e.g. for corporations e.g. www.portfolio.mycompanyname regarding influence on ranking and PageRank?