Overclocking is not just the CPU.
Whilst the rest of the article was pretty yawntastic, the bit about overclocking caught my attention. Overclocking is a tricky business in designs not built from the ground up for OCing. Your ideal is a design that has a separate power feed and clock for the socket so you can ramp up the power and frequency as you go (in simplistic terms, to push cycles faster through a chip means using higher voltages, which is why OC'd chips get so hot). Problem is, many designs use the same clock and power feeds for the memory and IO bus as they do for the CPUs, which means changes in clock and voltage for the latter impacts the memory and IO devices. And that can be real trouble, causing signalling issues, overheating or just plain failures in components built to standards that are being exceeded by the OC'd system.
So I don't think it will be quite that easy to OC the SPARC Ts. If you look at PC mobos that are designed for overclockers they have software tools and hardware additions to allow you to change the socket clock and voltages without affecting the memory or IO. I'm not sure if they exist today for the SPARC Ts so that may mean a redesign of their mobos. This isn't just a problem for SPARC, it's the same for Itanium and Power, they usually have mobo designs built for reliability rather than overclocking.