version 2.1.0 (07/28/2007):
libpurple:
* Core changes to allow UIs to use second-granularity for scheduling.
Pidgin and Finch, which use the glib event loop, were changed to use
g_timeout_add_seconds() on glib >= 2.14 when possible. This allows
glib to better group our longer timers to increase power efficiency.
(Arjan van de Ven with Intel Corporation)
* No longer linkifies screennames containing @ signs in join/part
notifications in chats
* With the HTML logger, images in conversations are now saved.
NOTE: Saved images are not yet displayed when loading logs.
* Added support for QIP logs to the Log Reader plugin (Michael Shkutkov)

Pidgin:
* Ensure only one copy of Pidgin is running with a given configuration
directory. The net effect of this is that trying to start Pidgin a
second time will raise the buddy list. (Gabriel Schulhof)
* Undo capability in the conversation window
* The formatting toolbar has been reorganized to be more concise.
* A new status area has been added to the top of conversations to
provide additional detail about the buddy, including buddy icon,
protocol and status message.
* Show idle times in the buddy list as days, hours, seconds

Finch:
* There's support for workspaces now (details in the manpage)
* There's a new custom window manager, Irssi
* Some improvements for tab-completion, tooltip and the password entries
* Some bugs regarding search results fixed
* A new DBus-script to create a docklet for finch
* Support for showing empty groups in the buddy list (Eric Polino)