flight86, i believe in general, the rejection email after the 1st interviews comes quite quickly (within a few days).
Hence i would say if u still did not receive anything after a week plus, there's a decent chance u r safe. But of course, there are the exceptions too.
Anyway, gd chance now to find out more about the tougher qns posed to u in the first interview, in case u get called up for round 2
