From the Add Post screen? The problem just started either today or late last night.
I can access it fine from the left main nav, but if I go into a post and click either on Upload/Insert or Add Featured Image, then select Media Library, it drives the Google Chrome Renderer instance (OS X Snow Leopard, Activity Monitor) to nearly a GB of memory usage and crashes the tab.
There are no new plugins, no updates to plugins, nothing. It happens to any post so there isn't a corruption in the content causing it. I've also run Repair & Optimize on the database and it doesn't make any difference.