Some people say accommodation is big and spacious, some say small...what is this in comparison to? In the states, most accompdation is very big, yet here in England it is quite small in comparison.
Depends where you go. Khalifa B villas are quite big, really. Apartments in Musaffah and downtown are not as big as a villa, but still very large compared to anything you might get in London.
The new places coming up in Al Reef are said to be considerably smaller.
Also, regarding the apartments - I have tried to google some photos but can only find a video on YouTube of a cabin crew dorm which looks pretty dark and dingy...is the pilot accom different to this?
Depends entirely upon where you are. The places within Etihad Plaza are modern and convenient, but not exactly very beautiful. More of a hotel-atmosphere.
And when you are offered a contract, is it possible to put a preference for certain accommodation?
Yeah, you can state your preference.
And final question...I presume the apartments all have swimming pool, gym etc? What is the social life like around them compared to villas?
Nope. Some places have that, if you are lucky. In Musaffah, the swimming pool is a joke - it's tiny, it's indoors in a cellar, and with very doubtful hygienic standards. The gym is quite good though.
If you move into a villa, obviously there's nothing of the sort, you either need to join a club (which is VERY expensive), oder always drive to the company's fitness facilities that you're allowed to use.
Social life is virtually nonexistent. No BBQing, no partying, everything is forbidden. All you can do is to find some friends on your own, visit them and go out with them, but there is no neighbourhood around your accomodation whatsoever.