LordAro

As of 1.7.1-prerelease, this is still happening, needs reopening

You have touchscreen mode turned on.
Suggestion: turn it off 😉

In other words, if you can reproduce the issue on an unmodded server/client, resubmit the issue report

Still water does not slow down the player (any more), therefore flowing water shouldn't affect the player either

Also needs reopening 😉

In fairness to OP, MC-1644 has no labels, and the title isn't really related to this issue

In that case, are you able to give yourself this block with the /give command? If yes, see above comment
If not, disregard everything i say :L

Strongly Disagree: Nothing that is distributed with Minecraft should be able to crash the game. ever. Even if the user is stupid.
Using the /give command incorrectly shouldn't cause a crash
Edit: Disregard that, but the above comment still stands

By an admin/someone with creative?

Try going back to where you were - sometimes wolves have issues following the player if their chunk gets unloaded before they can teleport to the player

Try without fancy graphics.
If it's fine, leaves are broken 🙂

...or that your Minecraft installation is (for some reason) having to re-download the sound files but hasn't finished yet?

Screenshot?

Also occurs in 1.4.4 (and i assume 1.4.5), if you want to update the "Affects Versions" field

I strongly disagree that this is not a bug - the client should never crash, it should always handle user errors gracefully

In this case, making sure that selected blocks in the menu are not all transparent would suffice, i'd have thought

Will probably also happen with endermen

Will be fixed when the new lighting engine is finished

Very old, very known bug

I have also experienced this, presumably upon coming into an unloaded chunk (it was not me who 'spawned' the fireball in the first place.

I think it should be noted that the fireball was not stationary, but moving slow, although a lot slower than it should have been.

Intentional, due to scaling issues.