The underlying data structure will also be familiar to Microsoft SQL Server users; Caspio has SQL Server running underneath everything. SQL back ends are useful for programmers because they make it easier to link the system with other tools that expect to find an SQL database minding the information. The data ends up in a format that's comforting to the DBAs, and all of the unrelenting logic of SQL comes with it. I remember enjoying the fact that Coghead uses a more flexible XML database as the back end because it liberates you from creating a table for every single collection of items.
There are other ways that Caspio will be familiar to programmers and slightly confounding to the nonprogrammers. The look and feel for a data page is built out of CSS and a wizard. Pushing the "deploy" button assembles the parts in much the same way as pushing a "make" button. Other competitors do a better job of building WYSIWYG environments that let casual users plop down a field wherever they darn well please. As a programmer, I like Caspio's solution, but I suspect that the rest of the world may enjoy the WYSIWYG alternatives.
Bridge to Office
There are several other nice features that Microsoft users will appreciate. Microsoft Office applications can suck down data directly from Caspio using plug-ins. This tight integration lets you tweak the data to create charts and ad hoc reports on your desktop. It's not the same thing as a shell account, but it has some advantages for everyone. Caspio is also expanding the widget tools to make it easier to integrate your data tables with other sites.
The most promising market for Caspio will continue to be the casual programmer from a large Microsoft house. This set includes the people who aren't in the IT department per se, but who can do more with spreadsheets than just fill in rectangles. Many Excel users find they need to a way to make the Web site collect data or display it for the customers. Anyone with a good intuition for how computers work will be able to accomplish this, even if they don't have any formal programming training. The data can then be brought back down to Microsoft applications, where it can be massaged as needed.
Caspio Bridge can do more than just replace desktop databases -- it can also replace parts of Web sites. But that's life during the creative destruction era of Web 2.0. Caspio is a good, solid tool with a polish that will be welcome in many Microsoft houses.