Hi Nick,
Some diferences between filters and Advanced segments...
1) Segments are retroactive, meaning you can apply an advanced segment
on historic traffic, filters only affect new collected traffic (HUGE
DIFFERENCE)!!!!
2) Segment operate at a visit level. filters instead work at hit
level. A clear example of this would be an advanced segment with a
condition to include content pagename equal /pageA.html. The result of
this advanced segment will be all visits that viewed /pageA.html
including all other hits (pageview, events and transacctions)
generated by those visits. A profile with a filter to include traffic
with request URI (pagename) equal to /pageA.html will only include the
traffic to that content excluding all the other activity from the
visits.
3) A profile with filters applied generates unique visitors metric for
the profile. An advanced segment doesn't report unique visitors.
4) Advanced segments rely on sampling to generate some reports that DO
NOT use sampling at a profile level (for example keywords report).
This means that a profile that includes CPC traffic can report more
accurate information on long tail keywords than the advanced segment
that includes CPC traffic.
5) Segments consider a (Condition1 OR Condition2 OR Condition3) AND
(Condition4 OR Condition5) logic. If you want to define a profile to
include filters with this logic is not so easy.
6) Advanced segments support negation matches does not equal, does not
match regex... I'm not sure if this is posible with filters (maybe it
can be done within the regex but I haven't found a way :( )
7) The GUI to define advance segments is soo much friendlier than the
one to define filters!!!!
Cheers,
Andrés