I was unable to find this feature in Excel 2007. Doesn’t mean it isn’t there.
This function works in Excel 2007.
Function CountBold(r As Range) As Long
CountBold = 0
Dim c As Range
For Each c In r
If c.Font.Bold Then
CountBold = CountBold + 1
End If
Next c
End Function
However, a change to formatting is not considered a change to the cell so will not trigger an automatic recalculation of this function. You could declare it as Volatile, but even that won’t guarantee it will be recalculated when formatting changes.
Bite your tongue 
Actually, people come here because it’s handy and quick. That’s the tradeoff of a general-purpose board. Big audience who know a little about everything. Specialized boards know everything about a little. I happen to like www.ozgrid.com for Excel help, and I guess there are others that are very good too.