Getting this in 11b as well. Two attachments with F3 showing the faces it's chosen to grow in.
A friend of mine was suffering from this bug. I got him to increase his RAM allocation to Minecraft from 1GB to 2, and it seems to be running as normal. No idea if this change directly affected this bug or if it's a coincidence, but worth a shot at least while we await a fix.
Some very extreme examples of this. VERY extreme.
Reporting the same issue. Occurs in 13w19a Minecraft from the new Launcher, on the main menu screen (SP, MP, Options screen). First attempt to resize froze the entire computer within seconds. After reboot, tried again; froze in a similar manner after a few seconds again, but then the program shut itself down rather than making manual reboot necessary. In both instances, the screen froze in place and was inoperable, but the mouse could be moved around as normal, albeit unable to interact with anything. Sound continued to play normally from an in-progress source until the video ended, so there weren't any death screens that I recieved.
I'm afraid I can't give much useful information other than to confirm that I've witnessed the same bug, but hopefully this may come in handy. OSX Snow Leopard 10.6.8.
Found this in new chunks in 1.8. Seems to have only occured in a single forest biome, although in said biome it isn't rare. Only missing blocks appear to be logs and leaves of oak and birch trees, appearing to be cut off in small sections, probably along the borders of chunks.
Example included in picture.