your predicament is so familiar to me, believe me!
I placed an order for the 46 hx903. I waited and waited, got fed up, bought the Philips 46 PFL9705, sent it back because the 3d imagery had issues, contacted my local Sony and they happened to have a cancelled order on a 52 hx903 in stock. I asked them to wait for the WHF review to come out - they laughed at me - so I gave in under the strain and bought the 52. - it arrives tomorrow, just a few days ahead of the WHF review, which will probably advise there is now better on the market!
Seriously, go back to Sony, make sure you have the best current deal. You can get your VAT back on new orders now. You should also be able to negotiate a 3D package like the Panasonic - free glasses, receiver and Blu-ray.
If they say you can't have the latest best deal then go to someone else, is my advice. Also try ringing around as there 'appears' to be some stores with stock available for dispatch but you will lose your local customer service though.
Not easy. Wait until the WHF review comes out at the end of this week/next week and it will probably advise you to go for something completely different. Go for the one that you want though. compromise comes as a cost - trust me, I know!!! good luck.