advertisers are targeting certain age groups buying power in order to intice various age groups into buying their products or using their services. In order to do this the advertiser tries to associate the product with the consumer by using something familair to them. This could be an old TV show, a style of music whatever... this is most obcious in car commercials...
for example when the 2029 corvette comes out they will likely use music from bands like NIRVANA or PEARL JAM in order to plug the product to people from that generation who would then be in the 50 year plus age group and would be most likely to have the money to spend on a car like that.
i offer the following examples
example one - rolling stones with corvette
http://www.youtube.com/watch?v=NtxUBXBl_E4the typical teen-20's ager of 1968 when this song was released would be in his mid to late 50's at the release of this commercial. therfore it targets those who are in that particular buying group and have the buying power to go for a car of this type.
Example two
http://www.youtube.com/watch?v=CDdOErIdkX4the scion car commercial - it gives off a hip, youthful, inner city feel, and therfore targets younger people with smaller budgets as the target buyer for the car.
Example three
http://www.youtube.com/watch?v=OlMvStDmk3kBMW 5 series commercial. with an MSRP of just over $50,000 - again the target audience in this situation is the over 50 generation, therfore the commercial uses music from that persons late teen / early twenties life with the song "Pictures of Machstick Men" by the group Status Quo which was released in 1968 as well anyone who was around and loved that type of music in the late 60s would be in the over 50 age group and would probably enjoy the commercial.
its not just that music is getting better in the commericals, it is that the advertising agencies are getting smarter in the way they target consumers. If you think music in commercials is good... then you are either in the target consumer group or you just happen to like the particular song.
If you think the music is "Old" or you cant identify with it - well you are probably NOT the target consumer.