Some initial observations:
1. We were waiting for OBIEE 11g because we needed the OLAP presentation capabilities of OBIEE 11g to implement the project. OSA has had these for two decades, including: hierarchical drilldown (hierarchical columns in OBIEE 11g), custom groups (custom aggregates in OSA), and more OLAP capabilities.
2. OBIEE offers many more presentation opportunities. For example, in OSA, there are just reports and graphs. Now, we can add prompts, graphs, as well as the traditional pivot tables.
3. Adding attribute columns to a report is much more intuitive. In OSA, we had to create custom measures to simply add a column that had a higher level parent as a column in a report. Since OBIEE represents everything as columns, we can simply add those columns to a report.
4. OBIEE is more of an application development platform than OSA. We can create links between reports, add special prompts, LOTS of things.
Look for more observations in the coming days/weeks/months.