When airlines add routes or redesign their first-class seats, their public relations team shifts into overdrive, churning out news releases to squeeze every last bit of exposure from the news. But when the news is neutral, it's stop the presses. And when the news is bad, the airlines' cheerleaders are nowhere to be found. The communications tap is tight shut and consumers who miss the initial press release are left to ferret out the information on their own.

Where are my miles: Among the most irksome is the change to mileage expiration dates.

In 2007, most of the major carriers cut back the lifespan of miles in their programs from three years to either 18 months or two years.

We've now come to the end of that period, and those who failed to heed the airlines' policy change notices are finding their account reduced to zero. The losses can be huge, for some as many as 300,000 miles due to the new expiration policies. Assuming those miles were redeemed for domestic tickets with an average market value of $400, the expired miles would be worth $4,800.

The airlines claim they met their obligations in getting the word out regarding the new rules. Perhaps they did. But for many communication was less than a success.

Snooze-you-lose promotions: In November 2009, British Airways offered an unprecedented 100,000 bonus miles for signing up for their affiliated credit card and charging $2,000 during the first three months. Within a month, the promotion was replaced by an offer of pedestrian proportions. Then it was on again in January, only to be terminated yet again within weeks. The offer had been intended only for a select sub-group of its Executive Club members — a significant restriction that the airline failed to note in its marketing materials.

No more miles on Aisle 2: Safeway, a behemoth among the nation's grocery giants, is putting the kibosh on mileage-based marketing on Feb. 28, in favor of a "low everyday prices" pitch to customers.

Which mileage buddy: Late last year, Continental quit the SkyTeam airline alliance, anchored by Delta, and joined the competing Star Alliance, alongside United. Longtime marketing partners Delta and Singapore will be parting ways on May 15, after which members of the two airlines' programs will no longer be able to earn or redeem miles in each other's programs.

Southwest will no longer allow members of the American Express Membership Rewards program to exchange their points for credits in its Rapid Rewards program, effective from July 1.

That free trip costs how much?: The gradual ratcheting up of award prices is a fact of frequent traveler program life. But in the midst of a global economic meltdown? On Jan. 15, Hilton rejiggered its award chart, adding a new tier and recategorized many hotels as higher-priced awards. The average number of points required for a free room night will rise significantly.

How can you keep from being blindsided by nasty program changes? At a minimum, that means opening each and every e-mail from each and every program you're invested in. Read the fine print.

Second, the time and energy required to keep abreast of such changes, and their ramifications, is one of the most significant costs of participating in travel rewards programs. Pick a primary program and stick with it. It's much easier to stay current with one.