Well, bit the bullet and phoned up today to pay to pre-allocate our seats for our flight in a couple of weeks. It was £20 per person per flight, so we did it just for the outbound. In the end, I figured £80 was worth it to avoid the last minute panic of us being split across the plane - I just had visions of us traipsing up and down with a two year old deciding whether to sit with Mummy or Daddy. On the upside, we got 3 seats in row 18, so should beat the worst of the queues at immigration. It seems a lot of people are taking advantage (or is that the other way around?!) as it took me over 30 minutes to have my call answered, and the lady I dealt with said that they had been inundated with similar bookings all morning (today was the first day you can book). Anyone who has booked a flight already needs to call them, all new bookings can take the option at the time of booking.