Need a vote on chain stretch - take a look on pics

[bodyart27]

Just before the new year I did a valve adjustment so I took some pics to get an idea how much the chain has stretched since last time.

I will say that after six or so oil changes using mobil 1 every 3K miles - my valve train is looking sooo much cleaner than before:

What is this inside my valve cover? (Soot / Crud Rock?)

First pic - the valve train - looking better

Second pic - lining up the timing marks

Third pic - how the crank lined up first time around

Fourth pic - how the crank lined up the second time around

What do you think about the stretch??? Still OK??

Car has 209K miles.