I know the topic has been discussed to death in the early days of SSDs and I know that some tests have shown back then that you'd be better off upgrading your CPU than your HDD (mostly due to random write performance). UPDATE Refer this 1 year old community wiki question.
Now though, with cheap drives like the Corsair Force F40 offering good all round performance, has anyone made the step from old-ish HDD to new SSD?
My gut tells me upgrading my core system (Motherboard + CPU) will be much more expensive and the gains won't be the halving of build times, but I can't find any substantiated testimony on the internet about new SSDs + Visual Studio build times on slightly older systems.
UPDATE My system specs for reference: Core 2 Duo 2.8Ghz, 4GB Ram
UPDATE 2 Refer this blog post where older SSDs were tested and didn't improve compile times.