Circumstances under which I can take a user of an Apple desktop computer seriously:

1. they don't mention they have an Apple unless prompted somehow (general 'what do you have' discussion, direct question, etc.)
2. they don't use a keyboard made by Apple
3. they don't use a mouse made by Apple
4. they do not ever complain about Mac OS (because they know its tricks, and can therefore sort of be forgiven for using it)
5. they realize their hardware cost a lot more purely because it looks a certain way
6. they do not ever complain about being short of cash