Kathyinmo has a thread going about disabling a bunch of her browser's add-ons and the site runs smoother for her now. Do you have a lot of add-ons running? If you are running IE, click "Tools" and select "Internet options." In that window, click the "Programs" tab and click "Manage add-ons."
It could also be on account of the recent conversion and things may not be running as smoothly as they should just yet.