Both have had their problems. Blogger has been by far the worse, and I've looked seriously at moving somewhere/anywhere else. So, after 3 weeks of good service, I'm happy to say Blogger is doing far better than they were. Maybe they've turned the corner.
Bloglines has been pretty good, but about 5 months ago they moved to a very annoying version of the public view of one's bloglines collection. It was such a step backwards I took the link to that view off my news page. Now I can happily report that they've silently reversed course and reinstated the old view. I've restored the link to my bloglines collection.
Not all progress is backwards! Now if Blogger would only fix their Safari support, add blockquote to the BlogThis! widget, actually index the blogs more frequently than every other month, and put a shortcut to the full editor from the screen that appears when one submits a draft ...