Cruise expert or cruise geek?

How do you define an 'expert'? What's the dictionary definition of an expert?
Who's opinion would you trust?
I'm thinking about this because I was watching a show the other night that mentioned the definition of an expert was someone who had spent over 10,000 hours on one particular subject.
Being the geek I am a quick bit of maths work followed and I'm ashamed to say I can probably only get to about 5,000 hours talking about/studying/booking/sailing on/ thinking about cruises.
So does this mean I can no longer call myself a cruise expert?