Roll20 Wiki

The following is a summary of the releases of Roll20 updates, along with a link to the forum post/full changelog for each.

Introduced Status Effect Icons, over 50 icons to use to keep track of status effects and other information about your tokens
Introduced Roll Queries, a way to gather information to use in a roll or macro on a per-use basis
New token display settings to determine where (top, bottom, etc.) status effect markers should be shown, and customize the color of token bars for your Campaign
A new Deal to Initiative feature, very useful for games such as Savage Worlds which use card-based drawing to determine turn order. Matching new turn order sorting option to sort by card/suit.
Inline roll highlighting of crits/fumbles
Shadows for 3D Dice
New improvements to communication on the site, including PM archiving and editing and a Dismiss All Notifications button

Introduced the Transmogrifier, a tool to help GMs share resources between their campaigns
Introduced Inline Rolls, a new roll tool which has more compact results and can be used to do "sub-rolls" inside of other rolls
Added floor() and ceil() functions for use in rolls
Fixed crashes relating to the 3D Dice system
Enabled Rollable Tables for ALL users (including Base/Free accounts)
Added chat history clearing options

Modules (collections of maps, tokens, sounds, characters, and handouts which are pre-generated and made into a Roll20 Campaign) were introduced. One free and one paid module were available at launch.
The Roll20 API was enabled on the Main Server for Mentor users.

Card decks were improved, with additional options for how cards are played to the tabletop, new hand management display, and a discard pile.
The API was further improved, including state object persistence between play sessions and the ability to create new objects

The Roll20 API was introduced
The Roll20 Wiki was unveiled.
New features for the Journal including tagging + searching journal entries, drag and drop re-reordering of attributes and abilities, players can edit Handouts, and more.
Custom turn order entries
Hide the right sidebar
Macro and abilities editor made easier to use