Since yesterday, I am unable to create a new map by importing a .kml
file. The process fails with the usual "We could not finish uploading
your file." error message. However, the file being uploaded is known
to be 'good'. In fact, I tried uploading a file created by using the
output=kml parameter against a working map. Even more curiously the
same file will open perfectly in Google Earth.

It was all working perfectly a couple of days ago. I have tried it on
two different machines, with three different accounts, all with the
same result.

Any ideas?