Contrary to traditional belief cats have good long-term memory and are intelligent enough to be trained as well as dogs (proof).

The different and specifically demeaning way they are sometimes perceived in (e.g. "cats forget their owners pretty quick" or "cats are not smart enough to be trained") is due to the same deficiencies of human common sense that give rise to other unwarranted and unjust disciminatory beliefs and behaviors.

Cats are simply motivated differently when compared to dogs, i.e. they are not "wired to please" as much as dogs are. Also cats have different habits and they show attention and love with different timing and mannerisms.

Here is a couple of links that among other things refer to cat long-term memory characteristics.

http://www.catchow.com/catcarecenter_emotional3.aspx?combinedID=21502
http://www.petplace.com/cats/paws-for-thought-cat-intelligence/page1.aspx