Among the short list of good (or at least, personally interesting) Python projects under development today stands SQLAlchemy. It’s a powerful toolkit for working with relational databases in Python, including doing object-relational mapping. It offers a lot more power and flexibility than SQLObject (Python) and ActiveRecord (Ruby), while still staying pretty close to those in relative ease of use (ie – no Hibernate style XML mappings).
Especially interesting is that SQLAlchemy is a SQL toolkit first, and O-R mapper second. It has a lot of support for query construction, compilation, native feature support, feature-agnostic support, pre-processing, post-processing, and more, that can also be used in the mapping layer. Already it seems like it’d be free of the kind of issues that I ran into when I tried to deal with a moderately complicated Inheritance / contained object scheme with Rails and ActiveRecord.