I contacted the developers and found out the following about the proposed London Bridge Tower:
"Demolition of the existing building on the site will commence in the autumn/winter of 2005,
with construction of London Bridge Tower starting in autumn of 2006, completing in 2009."
The existing building is the Pricewaterhouse Coopers building directly above London Bridge station and will be the tallest building ever demolished in this country apparently!! So expect plenty of trucks and HGVs in that area from this Autumn onwards!!
It is a VERY scientifically planned dismantling. I spoke to the developer's person some time ago, and cynical as I am about what developers say to 'community representatives', they do seem to have it fairly sussed. I dont remember the details of it, but both the demolition and the building work had obviously been carefully thought about with minimising disruption in mind. I'm sure it will still be difficult, but I for one was pleased and slightly surprised with the efforts they had made. The reality of course remains to be seen.
Appart from the financial constraints as mentioned by Rabbie, the timing of the work is all tied up with the London Bridge Station redevelopment, which in itself is all tied up with Thameslink 2000, and with rail finance. A tangled web of interdependency. I too would be interested to know whether anything has changed.