Travel search engine TripAdvisor has announced the release of its hotel popularity index, Reuters reports. In contrast to other hotel indexes which statically rank hotels alphabetically or by price, TripAdvisor's index is the first of its kind to dynamically rank hotels worldwide based on the popularity of a given hotel, as measured by both the quantity and quality of content written about it on the Web. Travel consumers can now refer to one Web index to gauge ever-changing opinions about more than 75,000 hotels worldwide. TripAdvisor regularly scours the Web for articles, opinions and reviews about a wide range of travel topics and retrieves links to comprehensive information about particular hotels. With links to guidebooks, newspaper reviews and user-submitted opinions, TripAdvisor's search technology retrieves hard-to-find information about a hotel - both good and bad. Using this wealth of information about hotels, the index assigns an overall score to each hotel and ranks all of the hotels in a given destination. www.tripadvisor.com United tops list: United Airlines has been named the airline with the best frequent-flier programme by Business Traveler magazine for the seventh consecutive year, Reuters reports. An independent research firm has conducted the annual survey of Business Traveler readers for the past 14 years. However, the question regarding the best frequent-flyer programme has only been asked since 1996, and Mileage Plus has won this distinction every year it has been awarded. With over 40 million enrolled members, Mileage Plus can earn members miles and awards for over 800 destinations in more than 120 countries when they fly on United or one of the 14 Star Alliance member airlines. Members earn miles when they stay at a hotel, rent a car, make a long-distance phone call, make a purchase on their Mileage Plus Visa, shop or invest online. www.united.com Winter winners: There is good news for business travellers in Britain as both Manchester and Birmingham airports increase services to many destinations worldwide for the winter. British Airways franchise partner Maersk Air is launching flights from Birmingham to Turin, Nice, Athens, Bordeaux, Venice and Toulouse and increasing flights to Geneva from six to 10 per week. British Airways is flying to Frankfurt five times a day thanks to one additional daily flight. New low-cost carrier MyTravelLite is launching services to Geneva. FlyBE will be increasing Toulouse services from four to six a week. Pakistan International Airlines is adding a fourth flight per week to Islamabad and Turkmenistan Airlines is launching a Monday service to Ashkhabad. There are also more services from Manchester airport. KLM flights to Amsterdam have been increased to eight flights a day and six on Saturdays. British Airways is increasing capacity on this route by using 49-seat aircraft on lunchtime flights. Rotterdam will be served twice a day by VLM. Next April, Qatar Airways will launch flights from Manchester to Doha. Return services will operate on Mondays, Wednesdays, Thursdays and Saturdays. Midnight express: Passengers arriving at Heathrow on late evening flights need no longer worry about missing the last train into London thanks to the Heathrow Express midnight service. The service departs Terminal 4 at 12.01am and picks up passengers from Terminals 1, 2 and 3 seven minutes later. Previously, the last train left Terminal 4 at 11.32pm, forcing some passengers to rush to catch it. The last flights reach Heathrow before 11pm, but the new service caters to those passengers arriving on delayed flights.