In 2012, ICANN started the process for the introduction to new top level domains. For $185,000, investors could pick a generic top level domain (gTLD) name extension and register it. As a result, more than 500 gTLDs were approved. Now, the sunrise period for some of those domains has begun, which allows trademark holders the right to register their desired domain names based on trademark ownership.
After the sunrise period, a pre-registration period begins. Many registrars will charge premium prices for people who want specific domain names on these gTLDs. After that, an open registration period begins.
There are legitimate reasons for wanting a domain name on one of these top level domains. I wouldn’t say SEO benefit is one of those reasons. Branding, yes. Strategic marketing, yes. Reputation management, maybe.
Before you go rushing off to pick up a domain name on one of these new domain name extensions, you should do your due diligence and figure out the value of the TLD as well as the domain name that you want. You should judge its personal value to your brand as well as the business value on the market. Chances are, some of those domains may do well in the search engines. However, many will not.
Search engine ranking policies change over time. I would suspect that Google and Bing would not rush to allow these new extensions to rank well right off the bat.
Likely, what will happen is the search engines will wait to see how these domain names are used then tweak their algorithms accordingly to discourage spammy use of them while encouraging legitimate use of them. Don’t think about buying a new domain name if you think it will give you a search engine advantage. It likely won’t and you will be stuck with a domain name that holds no value.