Just a short journal to bring a couple of things to the attention of future users.
1. The entry visa: You need a 30 day tourist visa for entry into Turkey. What that means is that on arrival, BEFORE you pass through passport control, you must pay £10 for a little stamp in your passport. A couple of things to watch out for here. Firstly, the little kiosk dishing the stamps out is on the FAR SIDE of the line of 12 or so passport control booths, and there is no signage telling you to go to the visa booth first. That means many people automatically join the lines, wait ages to get to the front, then get told to go and get a stamp and start again. So when you arrive you must WALK PAST all the passport control booths to the little kiosk on the end, get your stamp, THEN join the line. The second thing is that you must pay in your own currency (£, $ etc) and you must pay the EXACT AMOUNT - they don't give change. Worse, if you are travelling as part of a couple and offer a £20 note as payment for both people (i.e. £10 each), for some reason they don't accept this either. They'll keep the £20 for person number 1, then ask for another £10 for person number 2 - you have been warned.
2. Baggage - maybe it was a one-off, but I'd checked my bag through to Izmir, and after passing through passport control, quite by chance, I spotted my bag rotating alone on the carousel. So I rescued it and re-checked it. I can't say how typical this problem is, but again a word of warning.
3. Turkish Airlines: George W was in town for a NATO summit when I passed through, so maybe this factor might have been to blame, but I did notice that every single local departure with Turkish Airlines was delayed on the day of my visit. Not that George W causes problems wherever he goes, of course ... My flight was delayed three hours while a technical problem was resolved, however. This I know because I watched from the gate window while a team of eight technicians took an engine to bits then re-assembled it by torch light on the tarmac. Now I will admit that I held my breath during take off on that short flight.
On the plus side, though, the airport has an easy to walk and navigate route from international to local departures (10-minute walk), and a nice duty-free area. Signage and traveler info in the terminals is also good, as is cleanliness and temperature control.