this is a quite a difficult one to answer as it really comes down to what you want to get out of this. Both companies have pros and cons. Personally and it is only my opinion - if you are looking to have a career where the opportunity to work your way up the ladder is quick then Etihad would be the way to go but remember it is still relatively new and thus it is inevitable that there are teathing problems ie pay structure, housing and allowances however Emirates has been in the game a lot longer so have a pretty tried and tested regime so are much more stable however promotion takes a lot longer so it may take you anything up to 5-7 years to make a senior level where as in Etihad it can be achieved within 3 years if you display the attributes they are looking for.
And before everyone starts retaliating on this each company looks for different things at different levels and just because you are a senior in a company it does not give you the right to a CM or CSD position it has to do with your abilities. So although im saying it is easier to attain within Etihad you still have to be the right person for the job.
I hope this helps a little.
Both were excellant companies to work for
