(a) It claims that the Mac has 27-odd GB of data on the disk, which is interesting give that the Mac itself believes it's actually 30-odd GB.
(b) It's been going for just under seven hours now, and it's 9% done.
(c) That means it'll be finished in, oh, a shade under three days, total.
According to Wikipedia, Firewire should have a transfer rate of about 50MB/sec, implying that I should be able to back up 50GB in 1000 seconds, or just over a quarter of an hour. Whereas 9% done seems to work out at a transfer rate of about 0.1MB/sec.
Alternatively, it might be deciding "percent done" by number of files rather than number of bytes, but I'm always wary of backup software whenever there's a root-partition backup going on - it's too easy to just open /dev/whatever and start reading that, and wondering why you never get to the end.
Of course, it's entirely possible I've got the arithmetic completely wrong; it's late, and I'm tired.