Markdown accepts the <del> tag, which is very convenient if you want to remove a word, sentence, or paragraph but want to do this in a non-confusing manner. But many times you want to replace a word (say) with a new, more appropriate, word. And if you want to do this in a non-confusing manner, you need the <ins> tag as well. But Markdown doesn't allow this tag. Please change!
<ins>should look like? Green color? Imagine the spam of colors, it doesn't suit SO. If you want to add some emphasis on what's new I guess you could useboldand/oritalic.#888 boldseems ok. It would be a grayed bold. I'm not sure if I liked it at all :P. But I guess I wouldn't mind seen that around.#222 boldandboldlooks like the same :P