SQL Server 2008 and DTS supportability?
They (MS) said DTS will be wiped out after SQL Server 2005 and will not be supported, more and more SSIS is promoted to use. But within SQL Server "Katmai" DTS is included with a provision of management, run-time, and design-time support for DTS packages that were created by using the SQL Server 2000 tools and object model.
By using SQL 2008 CTP I can easily manage the SQL 2000 version DTS packages, though they are very basic ETL based packages to handle. As to use with SQL 2005 I have more practised with SSIS in this case.
As you are aware since SQL 2005 DTS and Integration Services are completely different products. There were times where community was under impression that SSIS is not a version upgrade from DTS, but it is. As it is evident you can easily manage and install both DTS and Integration Services on the same server. Run both DTS and Integration Services packages on the same server when both products are installed. Even if the SQL Server 2000 tools are not present on the server, you can run DTS packages by using the updated version of the DTS runtime that is installed with Integration Services.
The above are still applies to SQL 2008, with DTS packages that are created in SQL 2000 version can be saved in MSDB instance, for SSIS packages you can only save on an instance that is running SQL Server 2005 or a later version.
Within SQL 2008 using DTS designer you can modify DTS packages even if you haven't got the SQL 2000 on your machine, get more information about DTS designer from here.
Wait and watch for more supportability for DTS in SQL Server 2008 version.
Further links and refernces on SSIS:
Creating a Simple ETL Package Tutorial
Integration Services Tutorials
Microsoft SQL Server Product Samples: Integration Services - Home
Deploying Packages Tutorial