However, went ahead and downloaded 3.0.1 again and, sure enough... it crashed immediately! Looking at other threads it seems as though many people are experiencing this problem of iBooks crashing and no one seems to have found an answer to the problem. I guess I'll just have to forget about this app and use Kindle for my reading needs. At least that app has never crashed!
Apple has finally responded on another thread:
They are collecting info on the crashes and the message at the bottom of this page from firstname.lastname@example.org sets out the process for finding the crash report and sending it to him.
Looks as though this took Apple by surprise and at present they don't know what is happening - so, if you are experiencing crashes, check out this other thread and send your crash report to Apple.