If you are flying soon check out Seatguru – it gets behind the airlines spin and shows you the actual configuration of the seats on the plane. Use it to see exactly how much space you will ‘enjoy’, and what the best and worst seats are.
For business class travel check out the AirNZ 747 configuration versus Qantas 747 – see how the AirNZ business class seats have so much more space than their Qantas equivalents. That’s because AirNZ lie flat builds on the angled Virgin Atlantic pod system, while Qantas uses the older face forward system. Seatguru shows the Qantas business class seats as not completely lie flat, which is a poor substitute for the excellent AirNZ ones. (Which is why I’m about to fly AirNZ to Europe).
If you do fly AirNZ make sure that you partner with Virgin Atlantic, or stay with AirNZ for the whole trip, so you get the great seat pods all the way. Avoid at all costs AirNZ alliance partner United (or Untied as I call them), which offer only the appalling old part reclining business class seats across the Atlantic.
If you are travelling with someone else and want to chat, then British Airways offerings are not bad. The VA and AirNZ pods make it harder to talk or look out the window.
For a great site for customer reviews check out flatseats.com – BA reviews in particular are excellent. also on the site is a business class seat comparison table – note that no US airlines even have the angled lie-flat product – another symptom of their failure.