Just bought a brand new Porter Cable Benchto top table saw, see it
he http://www.porter-cable.com/index.asp?e=547&p=4946

While setting it up I found the machined aluminium table is slightly
concave from front to back It is consistent along the entire width of
the saw table. It looks pretty good from end to end. It is only a
poofteenth [14 thou] from being flat and am wondering whether this is
within acceptable tolerances for this type of saw.
Would they actually machine it like this on purpose? and if so why?

I have never owned a table saw prooir to this and really have no idea
to what sort of tolerances are acceptable.
Thanks
scul