A Google Webmaster Help thread has Googler JohnMu sharing a tidbit on how not to have your navigation menu structured.

The thread has a webmaster complaining his site dropped in ranking. It appears the reason the site dropped was because Google felt the site was keyword stuffing and spamming. Why? Well, he had most, if not all, of his site’s structure in the footer navigation menu. John explained this often might be confused with keyword stuffing and result in a penalty of some sorts.

John said:

Now I should add there are many sites out there, including this one, that puts a tremendous amount of the site’s structure in the menu and navigation. I don’t put it in the footer but I do put a nice portion of it in the top menu bar. Not all of it, because that just isn’t useful.

I do not know exactly how much of the site’s structure he had in his footer menu bar, but it does seem like he put it all there.

So just be careful how you handle your menu and navigation structure. Make it useful for the user and you should be fine.

Forum discussion at Google Webmaster Help.