List the arguments 'for' and 'against' GM (genetically-modified) crops?

Most of the "for" arguments for GMOs are false.  Still;

GMOs can make a plant or animal manufacture a pharmaceutical product.

 Against it;

Cross-pollinations have accidentally introduced drugs into the food supply

http://www.pacificviews.org/weblog/archives/002509.html

Cross-pollinations have spread GE genomes into neighboring fields and into the wild, not only injuring the capacity or farmers to choose non-GMO crops but even to injure the genetic variety in the native and wild fields.

http://www.gmcontaminationregister.org/

http://www.alive.com/880a3a2.php?subject_bread_cramb=635

GMO seeds can't be saved and thus engineer a form of crop-based feudalism or share-cropping

http://www.astm.lu/spip.php?article830&astm_lang=fr

GMO food crops are restricted to those that can be shipped for a market, thus they tend to supplant local food systems.  This has lead to dislocated farm families and workers, aggravating famine; http://www.faminegenocide.com/resources/facts.html

http://www.monbiot.com/archives/2005/12/27/how-britain-denies-its-holocausts/

Also unemployment, poverty, homelessness and illegal immigration.

http://www.globalpolitician.com/22241-immigration

BT crops engineer pesticide to be IN the food instead of "on", where we could at least wash some of it off.

Modifications cause us to eat things that cause unknown reactions, not just allergies but there are disturbing and not fully pursued evidence of causing sterility, genetic changes in the consumer, birth defects and other as yet unrecognized syndromes; http://www.biolsci.org/v05p0706.htm#headingA11

http://www.gmo-free-regions.org/fileadmin/pics/gmo-free-regions/conference_2010/press/Carrasco_soybean_PR.pdf

Glyphosate ready crops enforce mono-cropping.  Intercropping produces more "product" per acre and tends to maintain soils, while monocropping depletes soil rapidly

http://tinyurl.com/2592e89

Heavy herbicide and pesticide rounds injure both soil and those men and women who work the soil

http://www.i-sis.org.uk/GTARW.php

GMOs reduce crop diversity, which makes crops more vulnerable to disease

http://volensafrica.org/Loss-of-Crop-Diversity-Threatens.html?lang=en

GMOs reduce crop diversity, which are critical in finding crops suitable to survive marginal locations and weather extremes

http://www.fao.org/docrep/x0262e/x0262e02.htm

http://news.bbc.co.uk/2/hi/8182840.stm

Heavily damaged soils associated with this type of growing simply do not have anything left to impart strong nutrient values to our food.  This has led to an overall reduction in food value for every calorie we eat. <scroll to “Myth Two” http://digmybook.com/preview/155963944X/The-Fatal-Harvest-Reader

GMOs are causing activation of super weeds both by the rampant use of one kind of pesticide and by the intra genetic transfer of pesticide-resistant genes or simply pollens

http://www.nytimes.com/2010/05/04/business/energy-environment/04weed.html

GMO sourced drugs and anti-biotics are accelerating drug-resistant germs 

http://www.i-sis.org.uk/GMDNA_Does_Jump_Species.php

While GMOs promise lowered use of chemicals and the ability to rely on a single set of equipment expensesv, in truth after a couple of years, use of external chemicals rise and overreach the original levels fairly rapidly.

http://www.rodaleinstitute.org/20090625/nf1

http://www.truth-out.org/1215091

http://www.foodrenegade.com/vandana-shiva-on-the-dangers-of-gmos/ 

Now the superweeds, both with GE genes and those which have emerged from the wild, are forcing farmers to re-purchase equipment they had had prior to glyphosate dependence

http://biolargo.blogspot.com/2010/06/round-up-weed-killer-and-acquired.html