First, some definitions, in my own words:
A largely illegal and often insidious attempt to rob, harvest or duplicate information from another website without permission in an attempt to avoid the effort involved in creating great manual content and generate income, usually ad based.
Scraped sites would not typically acknowledge the originator or location of the scraped content.
A gathering and organising of various sources of relevant information from different websites into a central area, usually via importation of RSS feeds. Such sites are considered helpful to visitors in that they contain all the information required in one place without the need to trawl the net. Aggregation sites tend not to be ad or commercial heavy.
Aggregated sites should acknowledge the author and location of the content they import.
Google has recently said that it will downgrade ‘content farm’ type websites where most of the content is not original and is automated in some way. I worry that they may not make a distinction between the above two types.