You'll get a nicer room, but will not be upgraded to the Executive Floor as that is 'extra'.
The hotel has gone through a renovation recently and everything looks newer especially the gym.
However, be aware of the the very high cost of local phone calls. Like most London hotels, calls are still billed per 'unit' and a 15 minute local call (whether to an internet ISP or not) , I was charged over 15 pounds (US$20).
Be extra diligent in asking that your HHonors points be credited as this hotel is infamous for taking over 4 months in posting accounts. I had to post both of my stays manually.