The latest upload speed upgrades PDF does have final dates for all "being planned" areas:
http://shop.virginmedia.com/content/...e_13_09_11.pdf
Use as a rough guide, I'd expect 100mb to come 2-4 months after the dates in that PDF - that seems to be the rough figure for the lag between the two based on the current dates.. Certainly nowhere will be getting 100mb before upstream upgrades are complete, that's for sure.
My educated guess on RDNG would be Dec-11 or Jan-12
My area, being estimated Mar-12 for upstream upgrades, I'm expecting 100mb no sooner than April/May-12