Meanwhile, after 2 weeks I am still letting the one I am most looking forward to...the W2V London Blend...steep at least a week longer. The Louisville is so damn good I can stay with that while the London ages a bit more.
My two bottles of w2v London taste exactly the same at two years old as they did when brand new in May 2011. That's anecdotal, of course, and just my personal experience, but it tells me that London is one of those juices that doesn't need to steep at all.
I seem to recall that Louisville changed some with steeping, but I can't remember for sure, and it may be that, over the year and half I've had it, my palate changed rather than the juice itself. All I know for sure is that Louisville got very good somewhere between when I bought it (and didn't like it much) and now.