Removed: fnRender - fnRender was depricated in 1.9 and is now being completely removed here. Its always been a bit messy and is now superseded by mRender. The main reason for this is that DataTables use to take an independent copy of the input data source object / array. This is a performance hit and it means we can't do any binding to external objects (for example it makes Knockout integration almost impossible).
Removed: bUseRendered - with fnRender being removed, bUseRendered is irrelevent
Updated: With fnRender being removed we no longer need to take an independent copy of the data source object / array (since DataTables itself isn't ever going to write to it now - fnRender did and the copy was included so we didn't inadvertantly change a developers data source object without them knowing about it. This is no longer a problem, and in fact having it use the same data source object is extremely useful in many cases.
Fix: When using full numbers pagination in IE and clicking upon one of the numbers in the paging control, a Javascript error would occur due to trying to blur an element that was no longer in the DOM