Here is an example of what a PresentBlox enabled to support comments would look like:
<blox:present id="myPresentBlox">
<blox:grid commentsEnabled="true" />
<blox:data dataSourceName="QCC-Essbase" query="<%=query%>">
<blox:comments
collectionName="sales_comments"
dataSourceName="CommentsCollection" >
</blox:comments>
</blox:data>
</blox:present>
Once this has been done, users can right-click on data cells and add or view comments. No other steps are required by developers for basic comments support.