I've seen Topix come up a lot in Google searches when I have searched for local information. I don't see much use for it though because I already feel like I'm on news overload.
I found the "discovery" tool within google Reader to be limiting but the Google Blog Search was more comprehensive. You can even include dates in your search parameters and it indexed what seems like an endless number of individual blog posts. For finding feeds with it, I recommend doing an advanced search and searching for something "in the blog title".
Technorati featured too much advertising. It was on the sides but also in the middle of the page and that was a turn off.
Snydic8 seems like an interesting "from the ground up" approach since you can submit your feed for indexing and I liked seeing the stats on the approval status. But when I searched for "Cincinnati" it brought back only 88 results and most seemed like mainstream, commercial sources. Most of the results were from Topix. Some were from CitySearch. Others were from more established sites. Really I am not that into feeds that have huge followings or are from these larger sources. It seems too commercial for me. Though I did like how Snydic8 featured an overwhelming number of feed tags for different readers.
Here's what I added:
An Archivist's Miscellania
Archives Next
The Practical ArchivistThe Pondering Archivist
The Video Archivist
Academic Librarian
I also formally added 2 blogs I already read from time to time that I have on my Firefox toolbar:
Library Link of the Day
Reflections from a Small College Library