I'm on the same cabinet, and share your frustrations. The cabinet has been due for an upgrade 'within the next 3 months' for 2 years now. At the end of each 3 month period they just push the date out another 3 months. In the meantime we suffer with 1mb download speed (on a good day).
There are two places to look for updates on this.
type in your postcode (I assume GU12 5 something) and it will show you a yellow pin where the cabinet is. Right now it suggests there is a problem with underground utilities where they want to put it, so I assume they need to move it further along the Wharf.
Use the availability checker and it will show the same expected date as the other link (right now, 31 March 2013). Don't get excited, it will get pushed out another 3 months as soon as that date gets close.
I'm not sure how to deal with this, but I am thinking about writing to our MP. There are a number of local businesses served by this cabinet. Plus those of us who have the option to work at home can't use it because of the terrible internet connection (to have avoided a treacherous 4 hour drive home in the snow on Friday evening by working at home would have been nice!).
Sadly it's difficult to precisely quantify the economic impact on the community, but given it's hardly a wealthy area & a decent population mass, I would have thought they should be working harder to get us in to the 21st century.
Hope this helps