I've used my Apple MacBook Air now for over ten months and it has been on a USA road trip, a photographic retreat in Morocco and provided a mobile publishing platform using a 3G modem on a number of occasions. As a mobile digital darkroom I have no problem recommending the AirBook to photojournalists and general photographers alike. It may not be the most powerful laptop on the market but it has great battery life and fits into a camera bag with almost no noticeable additional weight to the normal lens and other cameras already carried.
More about the Apple MacBook Air Here