Impact Factor Again

Do low impact journals carry materials that are scientifically not up to the mark? Or, is it the other way round -- journals with high impact factor get an elevated status only because of an influx of large amount of papers and in the process a majority of them get rejected because the volume of the journal is restricted?
How do you actually capture the importance of someone's contribution through scientific publication?  Is it only the impact factor of journals (based on citation) to which the paper was sent , or the reach of that publication to common mass (who may not be researchers and may not write papers with a citation of other works), thus contributing to the society at large by improving the quality of life?

Whats your views? Follow the link for a high profile discussion on this issue from reputed editors of various journals.
http://www.wame.org/impactfactor.htm

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