• We’ve improved the formatting of the help file so things are hopefully a little easier to read.
• We have a new updated object model layout diagram.
• New files to give updated Intellisense comments.
• Some new samples in Visual Basic.
• Added ASF indexing support. For more information, see AsfIndexer in the Programming
  Reference.

• A new Mode property, EncoderSku, which gives more accurate SKU information than Mode.IsExpress.

• A new MediaItem property, FileOutputMode, which you can use to select ASF MBR as well as "Adaptive Smooth Streaming" output modes.

• Enhancements to how output files are generated and accessed.

• New audio overlay functionality for MediaItem.

• Two new AAC base profiles for AudioProfiles.

• Two new H.264 base profiles for VideoProfiles.

• A new AdaptiveStreaming profile for both AudioProfiles and VideoProfiles.

• A new VideoProfile profile, VideoProfileMbrDeltaCollection, which you can use to customize MBR and/or AdaptiveStreaming output streams.

• A new default resize mode of SuperSampling instead of Bicubic.

  Here’s the link to download the updated SDK.

  http://www.microsoft.com/downloads/details.aspx?FamilyId=9A077A3D-58CE-454C-B486-153F0578BE4A&displaylang=en

Source- Expression Encoder Blog