Some of these new improvements include more "netcode" and "tickrate" fixes, specifically for the "consoles" like the Xbox 360 and PlayStation "3".
Game Mode Improvements
General improvements and tweaks have been made to the following game modes: Rush, Obliteration, Obliteration Competitive, Capture the Flag and Carrier Assault.

Visual Recoil
Close and medium range optic reticules do not move with the gun any longer, however both bullet spread and bullet drop are still present.

Soldier Movement
Changes have been made to soldier movement so that it closely matches the one in Battlefield 3, but without compromising the visual fidelity. This change also makes it easier to get away from undesirable firefights.

Additionally, we’ve dampened third person hit reactions where the soldier previously moved his head around a lot when getting shot at

HUD Triage
Focusing on clarity, and de-cluttering the HUD/UI to only show what is important – we have added several options and functionality to make your screen much less cluttered (and give you a lot of choice in making it the way you want).

Revive Mechanic Improvements
A special effort went into making revives easier to use, more robust and easier to understand. Additions include a “fully charged” paddle sound, UI indication on revive time and better networked ragdolls.

“Netcode” Improvements
Making ping differences, trade kills and kills behind cover less of an issue by lowering the time allowed to damage on the client side.

Automatic High Frequency Update setting enforced with the intent of release to all platforms, including Xbox 360 and PlayStation 3. Improvements to bullet damage times from client to client, “dusting” and de-syncs.

Vehicle Balance
Identifying and tweaking the top vehicles in need of buffs and nerfs.

Weapon Balance
We’ve focused on maintaining a consistent Time To Kill (how long an average engagement lasts for). With the changes to visual recoil, the third person hit reactions and improved “tickrates” has been sped up somewhat as we still need to balance this with damage and recoil changes.

Suppression systems has also been re-tuned and made clearer.

What’s next?
The next initiative on the CTE will be called the Teamplay Initiative. Here we will focus on improving teamplay and the objective aspects of playing Battlefield. This will include everything from Commander, Squads, Field Upgrades and Game Mode improvements, features and bug fixes.

The CTE for this particular update has been going on for the past two months now and is about ready to be wrapped up and shipped to the public.

(via Battlefield blog)