Add Delicious to Typepad!

why doesnt typepad and delicious cut a deal so that i can add a module that lets any of my readers tag my posts? kevin burton has blogged about enabling his readers to tag him though i cant find it on his site. fred wilson writes about how blog tools should get better and easier to do tagging. tom evslin has hacked a way to add a 'tag with delicious' link to his typepad posts which i'll try to add. however, why couldnt tom or someone hack something simpler that would just let me put in tag words and hit 'submit' like on flickr. if i'm not a delicious user then ask me to register. or why make me register at all?