WXP SP2's features:

[phongn]

MSDN has an article up on what Windows XP SP2 will include.

In particular is support for NX (AMD64 has it in PAE mode, Microsoft is pressuring other hardware manufacturers to adopt it). Specifically, it will allow applications to define chunks of memory as non-executable, making buffer overflow attacks much harder. Some interesting discussion may also be found here in the ArsTechnica Battlefront.

[Faram]

Intresting.

There is a similar feature to NX in TDS-3, they call it exec protection:

The dynamics of TDS Execution Protection scans an executable on the hard-disk before allowing it to execute.

But it is a software solution.