So DAC 1.1 has been out for a while (since March 2, 2011) now. The big change is that the DAC "upgrade" process is now an in-place upgrade rather than a side-by-side upgrade. As far as I can see, you couldn't do a side-by-side upgrade in 1.1 if you wanted to. AFAIK, in-place upgrade is the only new feature in 1.1, there's no additional database object support. Guess they listened. And fast.

As a starter, realize that you need to change the tools to hook them into the appropriate GUIs. DAC 1.1 requires Visual Studio 2010 SP1 for the new in-place upgrade functionality. SQL Server 2008 R2 folks can upgrade to DAC 1.1 by installing the feature pack. This functionality will be available in the upcoming SQL Server 2008 R2 SP1 as well. You can use the upgraded SMO libraries to obtain the new functionality in PowerShell as well.

However, as you might expect, while DAC Framework 1.1 supports packages created using the earlier DAC Framework 1.0, clients still running DAC Framework 1.0 cannot process DAC packages created by using DAC Framework 1.1.

In addition, in the same timeframe, but not as part of the upgrade to 1.1, you can install DACs into SQL Server 2008 SP2 and SQL Server 2005 SP4 instances, but only using the APIs directly. The appropriate history tables are kept in MSDB. SSMS for SQL Server 2008 SP2/2005 SP4 doesn't support it in the GUI, but a SQL Server 2008 R2 version of SSMS connected to SQL Server 2008 SP2/2005 SP4 would support it.

SQL Server Denali CTP1 installs with a different version of DAC that appears to support 1.1 functionality, it doesn't support all the 2.0 features, but they'll likely be supporting DAC 2.0, which is currently in beta. We'll just have to wait and see about that. And the upcoming SQL Server Denali tool known as Project Juneau will support it, as least as far as I can gleen from the information presented at the TechEd US sessions in May.

The DAC 1.1 feature comes as four MSI files and will replace versions of:

DACFramework.msi
  Microsoft.SqlServer.Management.Dac.dll (version 10.50.1750.9)
  Microsoft.SqlServer.Management.DacEnum.dll (version 10.50.1750.9)
  Microsoft.SqlServer.Management.DacSerialization.dll (version 10.50.1750.9) 
SharedManagementObjects.msi
  All major components of SMO updated to version 10.50.1750.9
SQLSysClrTypes.msi
  Microsoft.SqlServer.Types updated to version 2009.100.1750.9
  SqlServerSpatial.dll (non-.NET part of SQL Server Spatial feature, looks like its installed side-by-side)
TSqlLanguageService.msi
  ManagedParser.dll (version 10.50.1750.9)

This post has also gone a little long (again!), so I'll cover DAC 2.0 in a separate post. Later.
 
@bobbeauch