You will need to use an iPhone-specific non-Safari browser as currently the BBC is not detecting Safari on the iPad as a mobile browser. I use VanillaSurf no problems at all to view iPlayer on the BBC site. You may need to manually go to the mobile site instead (I don't have my iPad here to check it out) : ie not bbc.co.uk/iplayer BUT bbc.co.uk/mobile/iplayer
I've tried various iPad browsers but had no joy. It's the need for an iPhone one I found that was required. NB you can then scale it up using the 2x button, and the quality is fine (though maybe when they do actually support Safari - or an iPad browser - it may be even better)
HTH