My ears pricked up recently when a technology panel at a conference I attended were asked: "What's the next big thing?" One of the things that emerged from the discussion was the growing importance of online customer reviews. This seems a natural progression. If you can book hotels online then why not explore reviews of the hotels you're considering through the same medium?

There's much debate and discussion about guidebooks and revised grading systems, and the long-published RAC guide is to disappear at the end of this year. Then I noticed in the pages of Caterer that Amberley Castle in West Sussex is to withdraw from the AA guide, its owner Martin Cummings and the AA's Albert Hampson having a spat in these pages about the guide's continuing relevance.

The reality is that the world is changing and that different media will work for different types and styles of hotels. The AA, and other guides, provide a level of quality assurance for those seeking it. Such grading systems provide a basis for measurement of a hotel's quality and facilities and there are people who have been relying on those measures for many years.

But there are limitations, and the case of Amberley Castle is interesting. It's graded with three AA Red Stars but the quality of the rooms and service would be considered by many to be nearer five-star, and so would its prices. But the limitations of a small hotel in a 900-year-old castle means it can't "tick all the AA's boxes", hence the grading.

Sites such as TripAdvisor and Yahoo Travel make it easy for customers to post their feedback and share their views, thoughts and experiences. It's up to date, compiled by several customers and tells it how it is, warts and all. Such a rounded view may inform potential customers of minor issues that won't bother most of them, but might strike a chord with the idiosyncrasies of a particular one.

Hoteliers should be aware of comments posted about their hotels online. Although they can do little about what's already posted, they can right the wrongs for the benefit of future guests. Get used to them - they're the brave new world.

Which is better - online or guidebook reviews?

Paul Boyce, general manager, Malmaison London
"I think it's OK that online reviews are being used more often nowadays - they require a lot less effort by the customer. There are dangers of online reviews, though, as they can be used to write nasty and damaging things. In general, online reviews give a true reflection of someone's experience of a hotel or business."

Kirsten Falk, general manager, the Roof Gardens, Kensington, London
"Professional reviewers for guidebooks look at all aspects of service, whereas guests posting on websites often mention only one or two things about a restaurant or venue. Guidebooks tend to be a lot more accurate, and I think their ratings are much more valuable to us than something on the internet."

David Wright, senior manager, the Witchery by the Castle, Edinburgh
"We value all our feedback very highly, and as such, we don't value one type of review over another. It's important to look at each individual review and evaluate how we as a hotel can improve. If we get a bad review, we investigate why the writer was unhappy."

Fiona Moores, general manager, Alias Hotel Barcelona, Exeter, Devon
"Online reviews can be useful, but they're a double-edged sword. I'd prefer people with a complaint to write a letter or phone the hotel, and not simply use the internet as a soapbox. Bad reviews are inevitably bad for business. On the flipside, however, it's fantastic when you read a good review online."