All..
You need to think about development cycles within a SW company. DLP released a new version in Fall of last year that was a revamp of the agent architecture. When Windows 8 was released (fall), SYMC was deep in building out V12 (soon to be released) of DLP and also some major changs to the agent architecture.
So they have their hands full, especially when it comes to the agent changes.
So to keep in line with DLP versions the next release V12.5/6 is where they will support the Windows 8 agent. Keep in mind that with each Agent release there is a possible need to also UPGRADE the platform, so there are other mitigating factors than just an agent patch.
In addition a mojority of Enterprise customers, not commercial, are not planning on using windows 8 in large amounts. This is why it may not be a huge priority for SYMC. They have done this with most of their other ENTERPRISE products.
Your best bet is to contact your SYMC rep and let them know how importnat it is and get more people to do the same. They will also be able to get you information on an official statement.
The squeaky wheel will get more attention.
I am just a messenger.. and know how things work with SYMC.
Please call solved if possible!