We just completed our compare of the spatial functionality of PostgreSQL 8.4/PostGIS 1.5, SQL Server 2008 R2, Oracle 11G R2 (both its built-in Locator and Spatial add-on). Most of the compare is focused on what can be gleaned from the manual of each product.
In summary, all products have changed a bit since their prior versions. The core changes:
I still haven't figured out where this R2 convention started. I thought it was just a Microsoft thing, but I see Oracle follows the same convention as well.
We are working on polishing off some suggestions in our last round of reviews and also incorporating changes from earlier reviews. We got perfect ratings in our last round. We also got two very rave blog reviews which we were pretty excited to read. One from Bill Dollins A Look at "PostGIS in Action" and Mark Leslie PostGIS in Action. It is always nice to know people appreciate your writing or even if they find flaws in it, have interest in it enough to comment about it. It makes all the effort worth while.
PostGIS in Action is available for Pre-Order on Amazon or Direct from Manning. The benefit of ordering direct from Manning is that you get the e-Book draft copy now and updates as we revise the chapters. The benefit of ordering from Amazon is that you can lock in a lower price. The price of our book on Amazon has been slashed significantly to $33.74 USD from its original $49.99 price with a pre-order price guarantee. I get a bit of a chuckle out of the fact that PostGIS in Action is ranked number 94 (at least for the moment) on Amazone in "Books > Computers & Internet > Hardware > Handheld & Mobile Devices" along side all those iPad application and Android books. I didn't even think of that as a market that PostGIS/PostgreSQL compete heavily in.