Data access: compare with IBM
IBM has recently release their own JS-based DB connectivity API. Unfortunately, they are quite restricted in terms of DB choice and Data formats selection. Let me give you a quick comparison of OAT's Data access layer with IBM Database Connectivity for JavaScript:

 OAT - data access layer
 IBM Database Connectivity for JS
 Data sources
 SQL, RDF, XML, Web Services
 Platform  Independent (Client and Server)
 Windows XP* (Client and Server)
 Application server
 Any HTTP (WebDAV preferred)
 PHP 5 with PDO extension
 SQL databases

*Windows XP is mentioned in the Requierements page. However, one may safely assume that JS code (Client) will run on any plaform. Similarly, it is mentioned that other DB/OS combo might work by using other, PDO-compliant server.