The Reblog feature allows you to blog anything that anyone else has posted and it allows you to blog it to all of your followers. It appears to operate in the same way that the re-tweet function on Twitter operates.
This is going to be great in getting people's older posts noticed. It should also help lesser known authors gain more exposure.
Also, it may possibly slow down the flood of new posts which might not be such a bad thing as long as it helps keep the better content circulating...
We will know the full effects of the changes over the next several days.