Why does it matter what temp. your airport card is? Its a laptop, they get hot, I wouldn't really worry about it, nor would I expect anything to get replaced. No two systems are exactly the same, no two environments are exactly the same. If mine runs at 50, and yours runs at 60, that could be any number of reasons:
1. ambient room temp
2. where the laptop is physically located
3. output power of the airport card
4. amount of general network traffic going on
5. etc.... etc....