Thanks for posting this subject. I went out and cleaned the outside portion of my dryer vent. First time in almost 20 years. It wasn't full, but there was quite a bit in there!
The clothes I washed today dried a lot faster!
I move my dryer out about once a year and clean the hose, and I have one of those long dryer brushes I use frequently. That is probabally the only reason mine wasn't completely stopped up!!