Reports are suggesting that Deutsche Bahn will, sometime later this year, be testing one of their ICE3 high speed trains through the channel tunnel. A successful test will probably mean that sometime in the near future DB will be offering high speed services to Germany from London. *Update – BBC reports that this will take place on Oct 13
When this happens it is likely that the trains will be running on the privately owned HS1 route which connects the tunnel to London. reports are suggesting that Abu Dhabi will be one of the bidders for the line, they will be going up against a Canadian pensions funds bid. August 17 is the final date for bids to be submitted and it is expected that the new owners will open up the line to other train operators. I would guess the money the UK government gets for the line will not be invested in the new High Speed route going North from London, that would be too much of a good thing.