Julie's Haunted Bookshop thread made me wonder what different readers expectations were for a cozy mystery.

Here is what I enjoy best:

1. traditional English country house setting

2. a strong female heroine (and I prefer *her* to be single) and good character development

3. not written in first person (this was discussed here, and since that time I no longer enjoy first person mysteries)

4. period mysteries- which at this time has me reading the Golden Age authors

5. location, location, location! I love being enveloped in rich details about a great sprawling estate, a beautiful cottage garden, the south of France...

Oops! I misread your post as what IS a cosy. Here's what I expect from one:

A cozy is typically a lighter mystery with no graphic violence, no graphic sex, minimal cussing, and minimal discription of the crime scene blood and gore. In many cozies, the quirky cast of characters and how they interact  are the meat and potatoes of the story while the actual mystery may take on a lesser roll. 

The sleuth is almost always an amateur, not a law enforcement agent, who gets involved because of some personal connection to the crime (a friend is a suspect, a friend was the victim, her business or home was involved somehow, etc..) Many of the sleuths are women.

Many cozies also have a rural or quiet suburban setting.