2011 bees pulse check

Temperature was around 55 and it was perfect weather to check on bees.  Even I did not have time to actual open hive and do a detail inspection, I was able to check under the top cover to see what is going on.  I see bees flying from all of the hive.  3 out of 5 hive are doing very well so I assume they are very strong.  Two hives are much-much weaker.  In week colonies bees are only on 2 - 4 frames while in strong hive i saw bees are on 6-7.  Also, I noticed new white combs at the top part of the frames, so I believe some nectar is coming in and queen is laing eggs.