I have Lifetime Elite with Delta, honored by my current main carrier Continental, but - not only do I feel for you guys, things also change - so I took an interest and did more reading on this, calling the airline about details. On United's site: "This policy is for travel exclusively within the 50 United States, Puerto Rico, U.S. Virgin Islands and Canada and applies to tickets purchased on or after February 4, 2008 for travel on or after May 5, 2008."
Before I forget, and Roatanman will like this: pony bottles are liable for $25 fees each way if the airline knows about them. TSA inspects bags and in particular tanks, but I don't think the airline has a right to look inside. I just wouldn't tell them.
Repeating some info, adding some...
Customers purchasing nonrefundable domestic economy tickets who do not have status in Mileage Plus or Star Alliance may check one bag for free and a second bag for a $25 service fee.
For 1K and Premier Executive Mileage Plus members and Star Alliance Gold members on any fare, the excess baggage fees will apply beginning with their 4th checked bag. For all other passengers, the excess baggage fees will apply beginning with their 3rd checked bag. Number of pieces in excess of standard allowance Excess fee: 1st, 2nd, 3rd, 4th: $100.00 per piece; 5th excess piece or more$200.00 per piece
Oversized baggage: checked baggage that exceeds 62 linear inches/158 linear cm (length+width+height) will be charged $100.00 per piece.
Overweight baggage: weighing more than 50 pounds as overweight. checked baggage weighing more than 50 pounds/23 kg will be charged $100 per piece.
If a checked piece of baggage is oversized and overweight, the charges will be added together.
I've often advised others who felt confined to 2 - 50# bags to just pay the extra $25 each way on one bag under 70#, but $100 is a big jump on overweight - don't even think about a third or oversize bag...!
International doesn't seem to be changing...
(excluding travel to/from Brazil, El Salvador, The Philippines):
Economy Class: 2 bags, maximum 50 pounds/23kg each free allowance
For 51-69#: $50 - could not find that on the site so called the agent; not as bad as $100, but still twice the $25 I was thinking.
Fees for baggage more than 70 pounds/32kg or exceeding the maximum linear dimensions vary by destination. Contact United or your travel agent prior to your trip for details.
There is a fee of $100.00 for each additional checked bag. Added charges apply if the piece is overweight or over size.