Yes, yes. The text of the report claims scientists are 90% certain of the report's conclusions about global warming. But look at the actual data, supplied graphically in the 2007 report. (click image to enlarge)
Their estimate of man-made contribution to global temperature rise is expressed as somewhere between 0.6 watts/m² and 2.4 watts/m². That is a variance of a factor of four. It could be a little, it could be four times that amount!
Also, note that the level of scientific understanding of many important factors influencing global temperature is still admittedly low. On the column farthest to the right, the "LOSU" (level of scientific understanding) of aerosols, surface albedo (reflectivity), contrails, ozone, is all medium to low.
The IPCC claims to be 90% sure. Are they 90% sure that their understanding of these important factors is low? It would appear so. Here it is, in black and white (and red and blue) in the graph published in their report.