This has been common practice for areas with concentrations of older
pedestrians for years. It doesn't surprise me that the Access Board would
propose doing it everywhere.

Yes, the rumor is true. AASHTO and NCUTCD have made a proposal to the MUTCD
team and if adopted will show up as a change in the MUTCD 2008 Edition. The
preliminary details are as follows:
1. Modify the walking speed used to calculate the pedestrian clearance time and
include it as a Standard rather than Guidance as in the current MUTCD.
2. Delete the existing Guidance statement that is being upgraded to a Standard
in Item 1. Also, for consistency with the walking speed included in the prior
recommendation, change the existing Guidance statement to note that a walking
speed of less than 3.5 ft/sec (rather than 4 ft/sec) should be used to
determine the pedestrian clearance time at locations where pedestrians who walk
slower than normal or pedestrians who use wheelchairs routinely use the
crosswalk.
3. Add a new Guidance statement recommending that the total crossing time
provided be calculated using a walking speed of 3 ft/sec and be based on the
pedestrian crossing from the location of the pedestrian detector or, if none,
from a point 6 feet from the curb face. The total crossing time includes the
walk interval and the pedestrian clearance time.
If the total crossing time calculated using the 3 ft/sec Guidance is longer
than the sum of the pedestrian clearance interval (as calculated using the 3.5
ft/sec Standard) and the walk interval, the walk interval should be increased.
It was noted that, for most applications on streets that are less than 100 feet
wide, the walk time plus the pedestrian clearance time (as calculated using the
3.5 ft/sec Standard) will meet or exceed the recommended total crossing time,
especially when the pedestrian detectors are located near the ramp and curb.
4. Delete an existing Option statement and replace it with a new Option
statement noting that a walking speed of 1.2 m (4 ft) per second may continue
to be used to calculate the pedestrian clearance time at locations where
equipment is installed to permit pedestrians to request and receive a longer
pedestrian clearance time.

Please feel free to contact me (as you have done before on CA Supplement
issues) if you need more details or specifics on this intended change. Also,
please be aware that only when the final text is included in the MUTCD, will
Caltrans and CTCDC review it to see if it is OK for California.

As I recall, the proposal was amended at the 2006 NCUTCD annual meeting; as
approved by Council, the walking speed to calculate ped clearance time would
still be reduced to 3.5 fps, but this statement would (still) use "should"
rather than "shall". Increasing clearance time generally results in a longer
cycle, and many pedestrians are already impatient with long cycles (and avoid
them by crossing against Don't Walk or by crossing at midblock locations). This
effect might be minimized by reducing the Walk interval to the minimum time
allowed, but with only a few seconds for legal entry of the crosswalk, the
temptation would be even greater for pedestrians to begin crossing during
flashing Dont Walk. This would increase the incentive to use countdown
pedestrian signals. In effect, the unwritten law seems to be changing to "Just
be sure you can finish crossing before the countdown ends". Where a pushbutton
extends crossing time for pedestrians, signal coordination can be affected,
resulting in less effective platooning of vehicles and fewer suitable gaps for
pedestrians who cross midblock.