This is what SecuROM v8.10.008 packs so far.

I've identified the following anti-debug techniques.

ZwQueryInformationProcess, the parent process PID is stored in the InheritedFromUniqueProcessId field of the _PROCESS_BASIC_INFORMATION structure, which is then used in an OpenProcess call, which opens the parent process. No idea what happens when the call is made.
CreateFileA on the parent process, afterwards call to ReadFile, SecuROM tries to read the PE header supposedly.
Then we have various calls to CreateFileA on various files like ntice,sice,jcdspy etc.
FindWindow searching for various applications's windows, some of which are at or over 10 years old.
A call to EnumWindows with a custom callback function.
NtQueryObject call to check for the DebugObject.
ZwQuerySystemInformation with the SystemKernelDebuggerInformation class(0x23) which doesn't seem to indicate a debugger under Windows 7 x64.
And obviously, calls to IsDebuggerPresent,CheckRemoteDebuggerPresent,GetTickCount,QueryPerformanceCounter,GetSystemTime.

This is by far an exhaustive list. I've barely scratched the surface.

On a sidenote, GetTickCount is proving to be much more difficult to beat. Because if GetTickCount is patched to return 0, I end up getting an error code value of 2001 meaning Win95 not supported, oddly, GetTickCount was introduced in Windows 2000.