THORmx wrote on Aug 12^th, 2010 at 12:15pm:

It's saying, I'll arrive at my next way point at "right now"...

The FMC is informing you "Now" a 'step climb' may be performed. You will notice on your map display a green 'S/C' is moving along with you. The FMC has calculated you may increase you altitude by 4000 ft. You may also notice that optimum altitude (VNAV page CRZ) is below what your new altitude would be. I prefer to use 2000 for my step value. Using step climbs is very common on long flights. As you burn off more fuel the aircraft get lighter then you can increase your altitude. This is absolutely essential if your trying manage fuel consumption.