Pros
If you believe in the brand then working for Apple is a dream come true. The people are friendly, for the most part the managers are competent. The discount on Apple products is good - up to 27% - and the occasional free iPhone/iPod helps to sweeten the deal.
Cons
Beware - there is no career development at Apple Retail. Vague statements like "the company is expanding rapidly - there are so many opportunities" and "you have to make your own positions" are used to stave off any criticism. This is particularly bad for "Mac Geniuses" because their role is technical in a retail environment there is no where else to go. Also, people performing exactly the same job earn different amounts. Because pay is considered confidential, if you raise this with a manager you potentially face disciplinary action for discussing your salary!