I added a new tag this morning. It occurred to me that some people might want a vegan tag, to quickly sort out things that have milk or egg in them. The way I figured out whether something was vegan or not was to look at the product website and check out their product info.
My method: I first looked at the allergen information. If an item said it contained milk or egg, obviously it's not vegan, and it didn't get the tag. However, if it did not say either of these, I quickly scanned the ingredients for anything obvious. I do not know all the "vegan pitfall" ingredients (as I'm now calling them), but if there wasn't anything obvious, I marked it vegan. I was kind of excited to find several items with a little badge saying "certified vegan" and went ahead and labeled all of those as vegan, even though I have no idea who goes around certifying things as vegan.
If you have other information about any of the products I've tagged, let me know and I'll remove the tag for anything incorrectly labeled vegan.
I cannot promise that the company will not ever change their ingredients to make something not vegan. If they change things and I don't notice (which I likely won't), let me know, and I'll fix my labels.
Basically, what I'm saying is that I am not a vegan - make sure to do your own research before diving into anything.