Unfortunately, I do not have a screen shot for a before, and you'll just have to take my word for this, but a single dimension usually runs around 4-6ms / tick.
What is this, you might ask? This is a 10x10x10 cube of wiring, all transmitting power in every direction. The pink cubes at the bottom left a re debug blocks that simply generate power, while the blocks in the top right do the same, but consume it.
What this picture actually shows is 1000 tile entities all distributing power in every direction, every tick, and only adding ~.5 ms to the tick time. The algorithm also does not allocate any memory while it is running, adding no overhead due to Garbage Collection. To drop TPS below 20, the mean tick time needs to go over 50 ms/tick.
Multiplayer
As you may have noticed, there is another player in that picture. I also tested the Assistants system, to allow other players to interface/remove your machines. Additionally, packet sending, GUIs, etc.It's all there, and it all works. Which is nice, because it should mean fewer surprises in the future.
I'm in the final stretch guys. Just a few more weeks (and one long conversion weekend) and I should have a 1.7.10 alpha.