There is a cycle route in Caen, near the Universoty, that uses the central reservation for a proper path. However, this dives under roundabouts using tunnels, so there is no faffing around at junctions. It's not too bad for its type, but I rather fancy that smaller sums will be spent on the London version.
Yes, this is often the problem with cycle paths in the UK. They are put in where it's easy to do. This invariably means that they where the road is nice and wide, and doesn't really need a cycle path, they put one in. Where it gets to a point where the road is narrower, the path disappears, often at the point that you most need it. The start and ends of paths are also often ill thought out, and require making sharp turns in no space.
Of course, this is all pre-judging things, and it may well be that a good job is done, but I guess that ultimately we will have to wait and see. I'm not overly optimistic though, as others have said, Boris has already cut spending on facilities in London.
Interestingly, on Queenstown Road at the moment, they have just removed some of the "on footpath" cycle path, and it looks like they are replacing this with some road widening, and hopefully appropriate road markings when they've finished. At the moment the way it's been done has created a squeeze point which could be worse for cyclists, unless they somehow delineate things.
This seems to suggest a turn towards a more sensible, and less segregated approach to cycle facilities. I'm slightly worried that Boris et al are suggesting a reversal of this type of approach.