Odd versions are unstable, even versions are stable. v0.2 and v0.4 are even/stable. v0.3 and v0.5 are odd/unstable. The next stable release will be v0.6. The stable branch takes bug fixes only - it does not change the JavaScript API, addon API, nor ABI (you don't have to rebuild modules after upgrading node with-in a stable branch).
The official name of Node is "Node". The unofficial name is "Node.js" to disambiguate it from other nodes.
Currently, by default v8 has a memory limit of 512mb on 32-bit systems, and 1gb on 64-bit systems. The can be raised by setting --max-old-space-size to a maximum of ~1gb (32-bit) and ~1.7gb (64-bit), but it is recommended that you split your single process into several workers if you are hitting memory limits.
