There's speculation that the global online letting giant is now facing its moment of reckoning after announcing it will verify all seven million listings on its platform for accuracy of photos, address, cleanliness and safety after coming under sustained fire from customers, state legislatures and local authorities around the world.

"This will have an effect on the number of listings, but it's difficult to say how much as we don't actually have much detail about how they're going to do it," said Reuben Schwarz of BnbGuard which monitors unauthorised lettings for home owners.

"To verify seven million listings will be a huge operation. But it still won't stop the bad actors as they can't make the rules too restrictive because that will hit their operations too hard.

"Their growth is already tapering down and they're under a lot of pressure to become a good corporate citizen after just being a Silicon Valley start-up determined to grow as fast as they could."

Airbnb declined to comment on the impact the new regime will have, instead sending out again the original announcement about the imminent verification with Airbnb chief executive Brian Chesky telling employees that it's a business fuelled by trust.

"But recently, events by bad actors on our platform took advantage of that trust, including at a home in Orinda, California," he said. "We intend to do everything possible to learn from these incidents when they occur.

"People need to feel like they can trust our community, and that they can trust Airbnb when something does go wrong. Today, we are making the most significant steps in designing trust on our platform since our original design in 2008."

Airbnb has come under attack through concern about its guests' behaviour - including horrific killings at a "party house" Halloween event last month in Orinda, a "bait and switch" scam in the US and a referendum in New Jersey. That demanded restrictions on the company, despite its own $US4.2 million advertising campaign to persuade voters otherwise.

Locally, it's also facing an Australian Tax Office crackdown on tax cheats who aren't declaring earnings and the prospect of new costly regulations, with the proposed imposition of compulsory short-term letting registries in NSW and WA.

Airbnb has campaigned against registers of holiday lets as they inevitably lead to a dramatic reduction in listings as hosts who don't have permission to let their properties or who've been evading tax take themselves off the market.

Listings fell 80 per cent when a registry was introduced in Japan last year. Airbnb's main rival in Australia, Stayz, is in favour of compulsory registries with a code of conduct backed by a three-strikes disciplinary regime for poor behaviour, and an industry body to adjudicate compliance.

"Stayz supports measures to provide certainty about the boundaries of the holiday rental sector in Australia," said Eacham Curry, Stayz corporate affairs director. "To that end, Stayz advocates for the implementation of compulsory and simple registration of all holiday rentals by state and territory governments across Australia.

"A state-based register of all holiday rentals will help confirm the identity of the owners and managers of short-term rentals to governments, industry and the wider community, as well as ensure that all properties subscribe to the ground rules for listing a property."

With Airbnb's potential stock market float next year, the global online letting giant is now keen to clean up its image, also launching a 24-hour hotline in the US so neighbours and guests can report problems which can be dealt with by a rapid response team.

Airbnb has been under pressure in many world cities where residents complain that benefits of tourism revenues are outweighed by the detrimental effects on local communities as holiday rentals replace residential lets.

The moves to verify the authenticity of lets follows exposure in online magazine Vice of a multi-level, nationwide "bait and switch" scam in the US, where guests booked into non-existent properties were conned into accepting sub-standard lets, refused refunds and given bad guest ratings if they pushed back too hard.

After the multi-homicide shootings at the Halloween party in California, Airbnb announced it would be monitoring potential party hires, specifically single-night rentals of large homes, a lot more closely.

Meanwhile, in Australia, the Tax Office says it has identified a $9 billion shortfall in holiday let revenue and is monitoring short-term letting websites, as well as using information from letting agencies to identify holiday let hosts.

"And we've found customers are a lot more scared of the Tax Office than they are of NCAT or any other bodies," said Mr Schwarz.

Airbnb, Stayz and other letting agencies are said to be cooperating with the tax authorities by passing on the details of short-term rental hosts.