Bukkit

Version 8: February 17, 2013

• Source Code

Added

• Portals smaller than 2x2 can be created using the force size parameter for the Create command.
• The ability to create portals can be restricted on a per-world basis using the abyss.world.<worldname> permission.

Fixed

• Fixed a bug when disabling the plugin when use-static-effect is false.
• Fixed a bug with EntityExplodeEvent when no blocks are going to be destroyed.
• Worlds may be specified by UUID for commands taking block or portal coordinates.

Version 7: February 16, 2013

• Source Code

Added

• Metrics using MCStats.
• use-metrics configuration option for enabling metric collection, defaults to true.

Fixed

• Bug when creating irregularly sized portals when the two size ranges don't match.
• The configuration descriptions now use WikiCreole, ensuring that a table of contents is available on dev.bukkit.org.

Version 6: February 14, 2013

• Source Code

Added

• Portals may be any dimensions and not simply square.
• Abyss can now load world scale and blacklist information from Multiverse.
• Emerald Block Portal Modifier, which uses Vault to interact with economy mods.
• Bottle 'o Enchanting Portal Modifier, which lets you make portals cost experience to use, or require a minimum experience level.
• require-square configuration option for enforcing portal square-ness, defaults to true.
• use-multiverse configuration option for enabling Multiverse support, defaults to true.
• slime-ball-strength configuration option for modifying slime ball strength, defaults to 1.0.

Fixed

• Portals now use SafeLocations, which can safely exist even when the world they're within isn't loaded.
• Exceptions during startup are now trapped, ensuring problems with the plugins file won't prevent the plugin from loading.
• use-static-effect actually does something now.

I haven't had the opportunity to do any performance testing on large servers yet, and no long term testing for memory leaks and the such has been performed. Minimal testing seems fine though.

There's currently no way for a normal player to get a portal wand, though they can use wands after they've been given them.

Some commands error out if used on portals in unloaded worlds. This seems like it should be incredibly uncommon to come up though.