I am a huge Google Reader user.
It took me a while to get on board that train, as before I was a huge Google Reader user, I was a huge lover of going to visit the sites I loved. I love seeing the entire site, not just the post. It was hard to let go of that. But let go (mostly) I did as Reader became easier and better to use and I realized how much time I saved getting everything in one place.
But what Google Reader is missing is an easier way to share what you love in your Reader. Sure, they give you stars for faving and an ability to share (with or without a note) with a few handful of people who opt-in through Gmail. And, they also give you a widget (what they call a window) that you can put on the sidebar of your blog so people can get a link to what you've recently shared (see the right-hand side of my blog for an example).
But I want to be Kottke, dammit. :) I want to easily be able to share an excerpt, a headline, a link and what I think of as a normal blog post. Flickr does this one click and I can share a photo right into my blog. Why can't Google do the same?
It would be a great service: you can easily share the great things you see and read right in your blog, and the original-writer gets correct links back, correct attribution, and all the rest.
So that is my wish. Somebody please invent this and then let me know about it. :) I will shout praises to your name right here in my little ol' Blog.