Once again, I had a stopover in Doha in July 2007 on my way to India and back home. Has the airport improved since 2005? Another reviewer told us that a new airport was planned for September 2006. However, I landed into the same airport as two years ago. No big changes compared to my experience two years ago.
Doha airport is incredibly crowded and way too small for an international airport. Queues are long but the staff are efficient and guide travellers towards the right queues. Security is not as tight as it was two years ago, probably because of the waiting lines. Once you get past security, you enter into the duty free zone on the lower level.
It is quite a busy duty free zone, but it was much busier two years ago, it is also one of the smallest duty free zone spaces I have seen for such an international airport. Qataris are busy buying alcohol and cigarettes (alcohol consumption is forbidden in Qatar) for their holiday getaway and many Western travelers have a look at the prices of the electronics (not cheaper than in Europe or the US).
If you are carrying bags with you, it will be difficult for you to wander in the duty free zone when it is crowded.
There are a few smoking zones in the airport but not the same as in 2005. In 2005, it was possible to smoke in an area protected by high glass walls which provided a full view of planes taking off and landing. Nowadays, Doha airport smoking zones are incredibly smokey and in a few seconds you are suffocating... It is best to wait until you have arrived at your destination to light a cigarette.
Toilets are numerous and relatively clean (but could be cleaner; there is water everywhere)
On the upper floor, there is a free Internet zone, where people can send emails and chat with family and friends. Once again, if you have a short stopover, it is not even worth waiting in the line. I personally had to wait for 45 minutes before being able to access a computer.
Also, on the same level, there are restaurants (mostly junk food), and several waiting rooms in front of the gates, less crowded than on the lower level. You can expect to find a seat to relax there while waiting for your flight.
My best experience of Doha has been Qatar Airlines, one of the best airlines I have flown with. Super service by handsome stewards and beautiful hostesses, super food, super seats (I had a free upgrade to business class because there were no seats available anymore in economy class).
Overall, Doha airport is an experience. It is a modern airport with modern facilities which has become too small because of the quickly increasing number of people travelling with Qatar Airways.