I also saw the pandas yesterday in the rather blustery weather. As some one who doesn't get all that excited by pandas (I saw them as a young child at London and remember them never really doing anything which when you're young is a bit boring) I went because I appreciate the historical significance of them for the zoo and UK zoos in general and because my partner was a bit more excited than me! I have to agree with the above that it was a very enjoyable experience, well organised and the staff's enthusiasm was obvious. The tour was about 15 mins which was plenty of time to get good views and ask questions, with only about 15 visitors present. Tiang Tiang was inside, mostly sleeping with a bit of scratching and yawning while Yang Guang was active the whole time walking around the outside part of his enclosure and coming pretty close to the windows.
As a new member (my first visit to the zoo was only this autumn after moving up to Scotland) I can't comment on the old enclosure, while these new ones didn't completely win me over. The indoors area was pretty small and basically just a cement square with some wooden edged steps/platforms to one side. I don't know all that much about panda husbandry and I know the zoo had to meet requirements to get the pandas so I assume that's all the pandas need but it does look quite bare inside and might put some people off if that's the first area they see. The outside enclosures are a different story-good size, well planted and with different areas with gravel, water, rocky areas and caves. I did manage to take a few long shots of inside and out (only on a regular digital compact though) so will try to put those up this evening.
Overall the pandas did win me over and I will definitely be spending more time down there in the coming year.