Effective today, Thai Airways have increased the baggage allowance for all classes of travel for all flights ...
Flights to and from America are excluded from this.
Economy class ... now 30kg of checked luggage (previously 20kg)
Royal Silk class ... now 40kg of checked luggage (previously 30kg)
Royal First class ... now 50kg of checked luggage (previously 40kg)
Carry on hand luggage limits remain as before.
The above info has been transcribed from the Thai Airways website. They are increasing the luggage allowances as a marketing effort to make the decision to fly Thai more attractive to potential customers. Great news IMHO