If you used the CSV renderer in previous releases of Reporting Services, you might want to take another look in RS 2008. We listened to your feedback: not only does CSV rendering consume significantly less resources and is faster in most cases, the CSV data output is generally more useful as well if you use complex report layouts (e.g. matrix).
As in previous releases, the CSV renderer output is customizable via device info settings and the data output is controlled by the DataElementOutput setting on reportitems and groups. For more information about report design considerations for CSV check the documentation.
One common question I have seen related to CSV output is how to configure different field or record delimiters. We improved this in RS 2008 so that you can specify special characters, such as tab or newline, directly in the report server's configuration file (RSReportServer.config). For example, to configure ASCII encoding and tab field delimiters in RS 2008 use the following settings:
<Extension Name="CSV" Type="Microsoft.ReportingServices.Rendering.DataRenderer.CsvReport,Microsoft.ReportingServices.DataRendering">
<Name Language="en-US">CSV (tab delimited)</Name>
<FieldDelimiter xml:space="preserve">	</FieldDelimiter>
Note: when using a server-wide device info configuration, special characters used as delimiters should be specified encoded. While this works fine in RS 2008, for RS 2005 please follow the approach described in the documentation.