I own and run a .NET blog. Lately I have noticed a disturbing activity.

When I write and publich an article I do not get top ranking for searches for that article but another site called superdotnet.blogspot.com gets the top spot.

for example this search here
shows my article on superdotnet.blogspot.com displays a preview from my article and a link to my blog. My article is nowhere to be seen in the search results.

Is this what is called scrapping. How can i stop this from happening.

Think of it as free publicity, without it your entry would not appear at all in the Google results by the looks of it. At least they are not ripping off your content and republishing it wholesale without any mantion of the original source. They are recommending your entry to others, publishing a short excerpt by way of preview with a link to the original in full.

Far from stealing traffic, I would be more inclined to think of this as an opportunity to drive traffic to you.

Thanks for the prompt reply.
In the meantime i have been thinking of setting up scraper sites myself. They seem to be an easy money making scheme.

And in your own words i would be doing webmasters a favour.