While it's true that people who get swooped out of their land could have taken precautions this is something that doesn't happen in reality, at least not at the speed it happens here in SL, which is seconds.
These problems can be avoided if the deeding procedure were altered. People have proposed putting in a listing delay. This would work. There is another approach needing only client-side change and you can eliminate swooping.
As it stands the default sell-to is (anyone).
All that has to be done are:
1. Set the default sell-to to (nobody)
2. Add a note or dialog that for a land parcel to become sellable, a buyer has to be indicated, and if you want the sale to be open you have to INPUT "


3. The checkbox should refuse to set if the land price is 0 or if the sell-to option still lists (nobody).
4. (addition that would add effectiveness) Before the land goes on sale open a dialog window and in larger than usual letters post "You have set the land (name and sqm parcel) for sale to (name buyer) for (price) - (confirm/cancel)