x100 now or x100S on Feb 18th?

To put things into perspective, you can buy the X100 for a little over the price of a the upcoming X20. In fact the X100 is just a bit more expensive than the RX100. Now which is the better camera?

IMHO the X100 going for around £500-600 in the UK right now is an incredible bargain. The X100S is twice that price but I'm sure not twice as good.
Wouldn't you spend £500 just for the amazing lens of the X100?

I'm keeping my X100 at least as a backup camera.