I think one possible solution to the diary glut is to allow people to categorize their entries.
I haven't put to much thought into the categories, but the types of entries I see a lot are:
Gaffes
Polls/Predictions
News Analysis
Personal Endorsement
Attack Entries, etc..
Once you get categories in place, people should be able to filter the types of entries they want to see.
For this to really work, readers should be able to alter the categories for mislabeled entries-- for example, if someone posts a nasty smear and labels it news/analysis -- people should be able to label it a 'personal attack' and people that want that type of entry filtered would have that entry filtered as well.
Thoughts?