Such is the nature of living in a shared database server. I can upgrade to a VPS for that, but it comes at a cost. I agree that the last few days, it has been slower than recent averages. Probably because the hosting company added more customers to the same database server.
I probably doesn't help things that we've been receiving a ton of spam posts over the last month. There are bot nets out there posting junk all the time... several hundred over the last few weeks, in fact.