By special features, I meant things that it wouldn't do yet.
The main special feature now is the 4 ways of creating the 3D PDF
Just the 3D PDF itself - this is good for embedding into Web pages.
(And a "special feature" we could add would be to create the HTML code for embedding the PDF into the web page for people who would rather copy and paste HTML code into their web pages.)
The 3D image area with titles, captions and body text.
The 3D image placed onto a raster background. You create a raster image for a background and place the 3D image on top of the other image.
Both a Background image and text. This is helpful for putting images at the top, left and bottom of a page, adding the 3D image and then adding titles and captions.
See: http://forums.renderplus.com/wiki/index.php?title=RPS_3D_PDF_Tutorial_-_Page_Layout
3D PDF placed on background image with text titles and captions.
Another important feature we added recently is "batch mode"
This lets you automatically create several 3D PDFs from saved .SKP files in a single operation. You create a batch file with the .SKP file names, the .PDF file names and a saved settings file, push a button and create all the 3D PDFs at once.
One of our clients has a library of 3D symbols and is using this to create 3D PDFs for each symbol which can be used by clients to preview the .SKP file before downloading it.
See: http://forums.renderplus.com/wiki/index.php?title=RPS_3D_PDF_Docmentation#Batch_Mode