Well, I do apolgoise. It turns out it was my updated video drivers that were causing the problem!
I really must investigate all possibilities before I go jumping to conclusions.
I'll have to take my problem up with NVIDIA. In the meantime, I have rolled back my video drivers and I am going to start using Plus! again.
Apologies once again, I was in a bit of a bad mood when I made the original post (as you can imagine).
So, no hard feelings, eh?