my ole' networks are niche oriented.. while it may be a bit broad, it does offer a wider menu for the surfers to choose from.. and with the inconsistency and stale RSS feeds generally out there.. you want to mix things up as much as possible....

on the other side of the coin, site specific blogs can have significant impact on search terms of uber targeted prospects... but the fact that they know the name of the site to search for.. does it mean good branding and they're ready to join or they just are looking for more free content by that site?