The September 2009 pocket Tube map. This is probably the most radical change it's had in at least one decade, possibly even two. Has someone been reading Maxwell Roberts?
Since March, the map has lost:
* the river (no map since 1924 has omitted it, I believe)
* the zone structure*
* the East London line buses** (it's now a line, "under construction")
* walk distances
* multiples of stations (if they're the same name, they're interchanges)
* info boxes in the map body
* indications of limited-time junctions (eg Kennington, Woodford)
* the "aeroplane" icons on main line stations that also serve airports
It's also gained more stations marked as interchanges (eg Paddington, West Hampstead) while Imperial Wharf is also there ("opening late 2009").
If it wasn't for the wheelchairs, this might be the most minimal pocket map ever.
* It's hard to believe it was as recently as 2002 that this was introduced, but it's true
** Or, as the old joke has it, "trains replace buses on the East London line"