They don't make them like they used to is a common refrain. It is however somewhat inaccurate especially in the appliance industry. Product has always been manufactured well with notable exceptions....The GE compressor recall in 1988 and The Maytag Neptune issues of 1996, but in general appliances last about 10-12 years.
You probably have not kept cars, clothes or furniture as long.
Over the last 10 years, there has been a push towards efficiency in appliances. California mandated it in 1986 (our present Energy Secretary) and the EnergyStar program was publicized. If you were replacing a 10 year old side by side with a new french door, what would be the savings?
With the recession, its a pretty interesting answer. First, there is $110 in energy savings. Secondly, there is a $50 Nstar rebate. For many manufacturers, there is an instant $100 rebate in May with a Yale matching rebate of $100. Then there are a few with individual rebates of $50. If you buy a refrigerator as part of a kitchen package, there could be yet another package rebate of $150-300.
Quick answer: At least $350 in energy savings and rebates on side by sides and french doors and up to $750 in packages.
Not a bad time to change your refrigerator.