I had updated successfully to 4.0c Beta 1 earlier in the day.
I went into logos.com and bought a March Madness sale title.
I closed Logos and restarted it.
I got the message saying there were new updates available:

I clicked to download available updates.
Before I noticed what was happening, Logos had crashed.
Log and crash file attached: 6052.Crash_2010-04-01.zip
It appears to be throwing an OutOfMemoryException, but I shouldn't be out of memory. I have 8GB of RAM, and wasn't doing anything else particularly memory intensive.