We get many requests on the Forum for the introduction
of effects categorization from users who find the effects
menu too long to easily manage.  This is merely the latest:
Is any developer prepared to pick up this baton and run with it?
It is one of the Highest-Rated Feature Requests on the Wiki and
is part of a formal proposal in the Wiki on Menu Reorganization.
See this particular sub-section:
You may remember that an early implementation of this was
trialled in 1.3.6 and immediately dropped due to opposition
from skilled power users. 
I think that this opposition will not re-assert itself this time for a
couple of reasons:
1) the proposal contains a feature to turn categorization on/off,
2) keyboard shortcuts for effects have been implemented, enabling
power users to mainly avoid using the Effect menu.
Thank you for your consideration,
Peter Sampson
Tel: +44 (0)1625 524 780
Mob: +44 (0)7732 278 299