Images left to right: © Bob Gibbons / ardea.com; new oil palm plantation © Greenpeace / Natalie Behring; soil erosion after deforestation © Sue Cunningham; tree stump © Rainforest Foundation UK; burning forest © Rainforest Foundation UK
How Much Are We Losing?*
In the past 50 years, a third of the world's rainforests have been felled and burned, and deforestation continues. The loss of natural tropical forests - both wet and dry forest - amounts to 15 million hectares per year . Of this total, almost 6 million hectares are humid tropical forests, or rainforests . It's the equivalent of about 8.5 million football pitches a year, or 23,483 pitches a day.
Although this deforestation averages a loss of less than 1% of the forests per year, it is believed that after the loss of 30-40% of a rainforest, the remaining forest will become so destabilised that it may collapse 
Brazil and Borneo
Mongabay.com notes that between May 2000 and August 2006, Brazil lost nearly 150,000 square kilometres of forest - an area larger than Greece. If those trends were to continue, in the next twenty years 55% of Amazon forests will be ‘cleared, logged, damaged by drought or burned'. 
Maps of deforestation in Borneo from 1950 to present, and predictions into the future highlight the speed of forest loss. Vast expanses of Borneo rainforest have been cleared since the second world war. Forests are logged, burned and cleared, usually to be replaced by farms, palm oil plantations or pulpwood plantations .
Disappearing in our lifetime
Given that by 2050 there may be very little rainforest left in large areas in the tropics, it seems that it's not just future generations that will suffer the appalling effects that losing the rainforests will have on the planet, but current generations too.
*All global figures concerning tropical forest cover and deforestation, including the ones included on this website, have to be approached with caution as the underlying data are subject to considerable uncertainty.
1: FAO Forest Resources Assessment 2005
2: Hansen et al, PNAS (2008)
3: Global Canopy Programme
4: http://news.mongabay.com/2007/0813-amazon.html (accessed May 2008)