It didn't get the tagging right at all. On my bookmarks I somehow ended up with hundreds of tags in total, making tags effectively useless. I made very rough tool to just bulk delete delicious tags. Tags were useful but a pain to manage

What do you think ideal tagging should be like in a websites similar to del.icio.us?

There should be some fuzziness probably. My tags were in hundreds because I imported bookmarks. Many tags were essentially same with an 's' I remember.

I have never used Del.icio.us. I've tried to access it through web-archive but most of the snapshot are redirecting to 301 response error. How does the tagging work in del.icio.us ?