JetBlue, in what may become a wave of increases by other carriers, has jumped the fee for a checked bag from $25 to $30 and for a second from $35 to $40.
No other carriers have joined, but there's a history of other carriers following when one has successfully added or raised a fee, and with fuel costs rising, they may be ready to follow quickly.
The JetBlue increase applies to tickets purchased after August 27. The airline's Blue Plus and Blue Flex fares will still include a free first bag, as will its premium Mint Service. The fee for a third bag will take the steepest jump, from $100 to $150, but few travelers actually check that many bags.
UPDATE: It appears the parade to higher fees has begun. Air Canada and WestJet, Canada's #2 carrier, have both posted similar increases.