Just back from two weeks in Ukraine so thought I would share some
comparisons I made.

Kiev has a metro system with three lines and three interchange stations
(think of a triangle extending at each point). Map he
http://www.kiev.info/print/metro_map.htm

There is a travelcard system, but, like Paris, you have to buy it in
the first week of the month. For most journeys, though, it's like New
York - you just buy tokens from the booth and it's one token per trip,
no matter how long or how short. I have to say that this really cuts
down on queues. When I arrived at Kiev Station after an overnight trip
from Lviv, there were enormous queues at the metro ticket windows. I
thought I would be there for ages but I had my token within about two
minutes, it was just so fast, as people weren't ordering extensions,
period travelcards, etc. Has a token system ever been used or
considered for the tube?

One interesting feature of the Kiev metro system is that the
interchange stations have different names for each line. As you can
see from the map in the URL above, Zoloti Vorota and Teatralna are
actually the same station, but the names are for the green and blue
lines respectively. The equivalent here would be Oxford Circus having
different names for the Bakerloo, Victoria and Central Line platforms.
This seems quite odd to me and I'm still not sure of the point to it.
Interchange can be a bit of a trek, but usually fairly direct and
nothing like the rabbit warren of some London stations.

The trains themselves are showing their age. All have transverse
seating. Not that that is any good to anyone, as the trains are
PACKED, and I do mean PACKED, at all times of day. I think I got a
seat once at 11pm, and that only just. Based on Kiev, London
Underground is operating at about 50% capacity in the peaks g. They
really know how to cram on, too.

The stations themselves all look fairly similar, and the signage is
terrible. This is one area where I've consistently found that London
stands out. In Kiev the stations only have a name once, somewhere in
the middle of the platform. You just have to get used to counting out
your number of stops. I don't know why signage is generally so poor,
not just in Kiev but in many foreign metro systems. Such a simple
thing to get right, and so helpful as well.

They reverse our system of having an electronic sign saying when the
next train is due; rather, they have a clock showing how long it's been
since the last train left. This can only go up to 10 minutes, so I'm
assuming that's minimum frequency. I saw it get to 9:57 at one point
so it was a tight thing!

The size of the escalators is amazing. The make the ones at Angel and
Leicester Square look like pygmies. Most people just don't seem to
bother walking either up or down as it's just too far. Having said
that, there is some sort of half-hearted attempt to have a "stand on
the right" policy, but this is widely ignored, although I did see a few
people remonstrating and telling people to move so they could get by.
They also use the LU method of having two escaltors operating to leave
the station but only one to enter the station to control crowds in peak
hour.

The system seemed to work well and certainly managed to transport huge
numbers of people, but I would say in terms of comfort and
user-friendliness London does better.