It's understandable that the folks who develop core have other priorities. But the comment feature has languished. Basic (or what I see as basic) improvements to moderation, settings and the front end UI could do a lot towards encouraging folks to use it.

I'd also love to see some basic, built-in spam protection - something that doesn't require site owners to register with a service like Akismet. To me, that is the biggest issue. Web professionals understand the need to install some protection, but I doubt other users realize that.

No matter how good or easy to use the comment system becomes, a deluge of spam is going to make it not worth the trouble for a lot of users.