Veeger & betts
There is no "standard" time for a scan. It depends on many things such as your CPU speed, the characteristics of your motherboard, how much memory you have, what size hard drive you have, how much is on it, what operating system you use, how you have set up your system, what other software is running and how well you have been doing your housekeeping, and the list goes on.
Keeping all of your data files on a different partition to your operating system and program files is a good way to start. After that you should ensure that temporary files and cache cleanouts are done regularly, and that the operating system drive is defragmented on a regular basis. Keep the number of in memory processes to a minimum. Scans are best done off line and certainly not with your browser open. Expect there to be some interaction during the Spybot scan from the AV system, and in this regard some are way worse than others. Using the setting "run program once at next system startup" will reduce the number of other things running during the scan and might help, as might doing the scan with the PC in safe mode.
Version 1.6.0.30 did have significantly reduced scan times, and many of us are really pleased with its performance, but that may not be apparent on all setups because of the points mentioned above.
In the end though, providing you have done all the right things, the length of time it takes to scan your machine is what it is. If you want to heat up your cup of coffee quicker, either make the cup smaller, or use two matches under it instead of one.