Bukkit

You can get a fairly detailed list of changes by looking at the revision history.

The main change in this version is support for tab-completion on nearly all commands (the /go and /setspawn commands lack support, as does the /general command). In addition, the /give command has been both nerfed and improved; it no longer supports the "name:data" format for items, though "id:data" should still work (and you could of course add aliases mimicking the format), but it does support custom potions, armour colour, and skull ownership. The removal of "name:data" format is likely to be temporary; it's due to a rewrite of how item names and aliases are handled, and will probably be reimplemented later.

Extended metadata in the /give command is handled much the same as enchantments. For skull ownership, the parameter is "owner=<player-name>". For armour colour, the parameter is "colour=<colour-name-or-hex>", with hex values preceded by a # sign (color= is supported too). For potions, the parameter is "<effect-name>=<power-level>" or "<effect-name>=<power-level>,<duration-in-seconds>". If not specified, a duration of 80 seconds is used.

The /iteminfo command also shows extended item data now, except for lore.

Some of the below bugs from earlier versions may still apply. There may be other issues. This version has not been extensively tested. Please report bugs on the issue tracker!

• I'm not entirely sure if "playerlist.show-invisible" works, or if the "general.invisible-info" permission works.
• Some of the help entries are incomplete (notably for /misc.mobspawn and /teleport.go). I can't figure out why this is, since the info is being added but Bukkit seems to be ignoring it.
• Potion data is a bit strange; if you give a no-effect potion it'll tend to think it's called "null" for some reason.
• To get help, you need to use the full name of the command including the category, so "inven.give", "chat.tell", "misc.time", "teleport.go", and so forth. This shouldn't be a major problem since the /help command lists them like this anyway.
• Aliases are missing from the help output.