I confirm, Visa on arrival is back to normal for the 33 countries.
Check the link from Qatari newspaper:
The Peninsula On-line: Qatar's leading English Daily
Visa on arrival rules for 33 countries stay
Web posted at: 4/19/2010 1:54:36
Source ::: THE PENINSULA
“It has, therefore, been decided that the existing visa-on-arrival scheme at the Doha International Airport for the citizens of the 33 countries will remain unchanged,” QNA quoted a senior Foreign Ministry official as saying.