The driver for this is to simplify things for the IATA industry members saving them costs, rather than for the public, although it is sold as a benefit to them as well.
This project was annouced last year and has seen the creation of a central database for carriers to reference the applicable baggage allowance both at the time of check-in but also at the time of booking (rather than relying on the old IATA reference books).
The International Air Transport Association (IATA) announced Automated Carrier Baggage Rules (ACBR), the latest project in IATA’s Simplifying the Business program. ACBR will provide a central database for interline baggage rules, enabling airlines, travel agents, and passengers to know what baggage rules will apply for any given itinerary.
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IATA is partnering with the Airline Tariff Publishing Company (ATPCO), who will host the central database. IATA will populate the database by mobilizing airlines to submit their baggage rules to ATPCO by September 2010 for implementation in early 2011.
Travel agents and airlines that link to the new database through existing reservations and ticketing systems will enable passengers to receive baggage fee and allowance information at the time of booking.
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IATA Press Release from 8th June 2010:
http://www.iata.org/pressroom/pr/Pag...-06-08-01.aspx