Magnus1:
I would like to see any articles on the peaking of world light sweet crude.

Please check out this link:
http://www.opec.org/home/Monthly%20Oil%20Market%20Reports/2005/pdf/MR082005.pdf

It is the OPEC August 2005 report. Go to page 5 paragraph 2.
 Basically they say that the future world refining capacity that is built should reflect the kind of crude being extracted, namely the heavier one.

Hope that this is the kind of information that you were looking out for.

Regarding the OPEC August 2005 report, both pages 4 and 5 provide some good information about the distribution between light, medium, and heavy oil, now and expected in the near future. My interpretation of the information provided is that the proportion of light sweet oil is expected to decline in the future.

Page 4 indicates that what growth has recently take place in light oil in the recent past is in light sour oil. Page 5 indicates that growth outside OPEC in the 2007 to 2010 period is expected to be predominantly medium, balanced between sweet and sour. OPEC capacity expansions in the same period are expected to be overwhelmingly medium and heavy and predominantly sour.