It just so happens that my favorite suit is a black Zegna.
Allow me to second the recommendation to wear a suit and tie. It shows you're taking the meeting seriously. Even if you're not competing for your job, it never hurts to impress your new bosses. However, I come from the school of thought that black suits are reserved for funerals or the evening. Depending on where you live, what your new business environment is like, a black suit may not be acceptable. I might recommend a grey or navy suit. On the other hand, I would certainly recommend going in what makes you the most comfortable (i.e. confident): if all your other suits don't fit right or have a stain or something, go with the black.
A shirt color other than plain white would be less formal; maybe a pale blue?
While I have often been impressed with pstoller's responses, I must respectfully disagree with this recommendation. I've never found pale blue and black to be an attractive combination - it tends to wash out the pale-skinned and yellow the dark-skinned. I do agree that a color other than white would be less formal.