You've probably heard about all the new functionality that comes BI 7.o , especially around web reporting. You can actually upgrade to BI 7.0 "as is" without having to do all the BI-JAVA stuff but then you won't be able to use the new web reporting functionalities that come with BI 7.0 like :
- New BEx Web Application Designer (Unicode, Command Wizard, ...)
- Exporting to PDF and Printing
- Integrated Planning
- Drag&Drop (Analysis Web Item)
- Web Items (Container Layout, Menu Bar, Tab Pages, Button Group, ...)
- Formatted Reporting with BEx Report Designer
- Document Integration with storage in Knowledge Management
To use the new functionalities you need a BI-JAVA stack, in essence a Netweaver Portal with BI business packages installed on it. You can either utilize your existing Portal or install a dedicated Portal for BI Web reporting.
SAP has a comprehensive note regarding setting this, see Note 917950 - SAP NetWeaver 2004s: Setting Up BEx Web. Also check the handy attachments to the note .
One thing I can add to this : Please try and run this on a 64bit Portal as the BI reports use a lot of memory on the Portal's J2EE. The reason for this is that the query data is transferred to J2EE as a whole during runtime, and we how big BI queries can be! (Note 996600 - 32 Bit platforms not recommended for productive NW2004s apps, Note 1044330 - Java parameterization for BI systems)