Notorious basically means 'famous' but has negative connotations (i.e it suggests the person or thing is famous for a bad reason)

Agreed. Notorious always has a negative tone, but I can understand the confusion. Sometimes people use it in a proud way, or with a positive spin. For example "He is notorious in the bars of Paris". This sentence doesn't say that the person is bad, but it does suggest that he is known to get up to no good (drinking, women, gambling, etc), and some people are proud of that fact.