Having worked for MS UK support I can vouch for the difficulties in manning support lines.
It's always difficult as you have a business model to "adhere" to - you're never going to hire more staff than you need as you end up with people not doing much, so the trick is balance.
The last year of my period with support was exclusively spent dealing with Web Support queries and I must say that this is a very good way of getting support for non-urgent issues but can be equally frustrating.
If you are going to use web support you need to put in all the relevant details. If you think 4 hours waiting for a phone call is bad then you are not going to be impressed if PSS take two days asking you questions because you didn't give the right info to start with!