I use Google Reader, currently subscribed to 68 feeds and get around 250-300 posts per day. I read everything in expanded mode, though most of the time I'll just skim a headline and move on.
I have my feeds logically grouped into prioritized groups so that if I start to get a backlog of 500+ posts I will read my favorite blog from a given category then mark all as read to reduce the counts.
I have my feeds logically grouped into prioritized groups so that if I start to get a backlog of 500+ posts I will read my favorite blog from a given category then mark all as read to reduce the counts.