Hi Hbrac,
The problem with all of these offers is that they put them on and take them off at will. Depending a lot on how well the sales are going. Last time we went on the Destiny, we got the free AI offer booking with Thomson, but it wasn't on with Portland, then our friends booked a few weeks later to come with us and got the offer with Portland
I do find generally the early booking deals do tend to be a lot better than the last minute deals, but ultimately it does come down to "is the price right for you?".
I have noticed though that the flights released this year are more expensive than the first release flights last year by about £125 per person to Cancun, Mexico. My personal opinion is that this is probably a lot to do with the high fuel increases over the last 18 months. But in the present economic climate, It is being suggested that holidays will be severely hit, so would also expect that the prices for last minute holidays will perhaps be more competitive.
I don't know, its a guessing game, the advantage of booking earlier is you get exactly what you want. We booked super early last year, as soon as the flights were released, and got a great deal that saved us £1400 on a family of four, but have decided to hang on for a late deal for next summers holiday as we will only be looking for something cheap and cheerful and are not that bothered where we end up.