Added way more levels (and mechanics exclusive to those levels), roughly doubling the length of the game. These can be accessed the same place the ending was originally.
A few tweaks to existing levels
Completely different ending
Added more music (including one more piece in the existing levels)
Some graphical changes: better title screen, trees in the background, boxes now have a checkerboard pattern, border in full-screen mode, snails rotate now, level transitions look different, there's now a way-less-subtle animation when a snail tries to jump but can't
There's now a bit of coyote time
You can now reset a snail's position by walking past where they originally were
Fixed a bug where a snail would behave weirdly if you were standing on them when activating them
changed/added/removed some text, mostly in the second half of the game
added a "Somewhat simple graphics" option, that only disables the effects that I know are an issue
fixed some issues that were causing the game not to work on some older browsers (now works on Firefox 3, though at least on the computer I tested on doesn't have a good framerate)
hopefully fix a bug where the snail sound repeatedly played (I couldn't reproduce it; I think it's when you die and activate a snail on the same frame, in which case it's frame-perfect)
The deepest screen now has a different color scheme than previously, and now has its own unique music
Subtle dynamics changes to some music
Found some buggy behavior when you ride an icicle down to where it breaks. Decided to keep the upwarp, but fixed the crash, and made it so you usually won't take damage if you hit the spikes during the upwarp.
Fixed a couple formatting issues on this version history page.