In reply to TobyA:
Having surfed a similar wave at Surf Snowdonia and see Kelly's wave, I think there is a massive difference between artificial surf and climbing. A key experience to a surfer in the shape of the wave and Kelly's wave has several and it is repeatable. You are also riding a man-made, but essentially nature wave. The pay per ride means that when you are surfing artificial waves there is no one dropping in on you, it is your wave each time.
My experience as surf snowdonia, was one of initial frustration but as soon as I caught the first wave, I waisted about one session perfecting this. After that each wave was among the best I have surfed. This is due to the very fickle nature of the 'perfect conditions' you need to make really good surf. Combine that with the number of people trying to catch those same waves in the sea, then artificial surfing has its appeals.
Whereas artificial climbing seem to avoid much of the experience. Route being set on indoor wall, means degrees of freedom through which we can express ourselves are limited. Even on indoor ice the routes get worked out and it is often simple hooking. Part of climbing is the environment was get to be in.
Arguably you could say the same about surf and the natural environment. However the movement on artificial surf is really good, almost a perfect point break. You also get to practice your frontside and backside surfing during a session. Allowing you to really hone technique.
I think that you can argue that climbing walls have help push climbing levels up and I happen to find indoor climbing for training fun, but my favourite part of indoor climbing is the gymnastic and athlete boulder problems. I prefer to climb on real rock outside but indoor climbing is something of a dirty pleasure.
For me the cross over between artificial surf and climbing are different. Although due to the price £40+ a hour for a surf means I save it for when I have some money. Whereas indoor climbing is something I could not live without over the winter.