Can I Travel to US for Holiday from my US Business Visa?

I have an US Business Visa valid till 2012, If I'm to visit US as a visitor on vacation do I need to re-apply for a visit visa or could I just use my valid Business visa?

OPINION:

I can't imagine how or why they would check.
They might ask you at the point of entry what
your business is and who your contacts are,
but I don't think it would go beyond that.
I think it would just be part of the general
screening process.

I think the real problem would be the other way
around - trying to do business (specifically working for pay)
on a tourist visa. In that case, all the checking would
be at the point of employment.

Or during your vacation you could do some business.
Or not do some business that was "planned".