No subject

Every person operating a bicycle upon a way, as defined in section 
one of chapter ninety, shall have the right to use all public ways 
in the commonwealth except limited access or express state highways 
where signs specifically prohibiting bicycles have been posted, and 
shall be subject to the traffic laws and regulations of the 
commonwealth and the special regulations contained in this section, 
except that: (1) the bicycle operator may keep to the right when 
passing a motor vehicle which is moving in the travel lane of the 
way, (2) the bicycle operator shall signal by either hand his 
intention to stop or turn, and (3) bicycles may be ridden on 
sidewalks outside business districts when necessary in the interest 
of safety, unless otherwise directed by local ordinance. A person 
operating a bicycle on the sidewalk shall yield the right of way 
to pedestrians and give an audible signal before overtaking and 
passing any pedestrian.

The full set of laws can be found here:
http://www.mass.gov/legis/laws/mgl/

The pointers to the sections most affecting cyclists are here:
http://massbike.org/bikelaw/



> 
> I was in the street, not the side walk, and I came to
> a stop before I did it (so I didnt just speed through
> the  intersection carelessly).

It matters none.  Legally you would have had to pull off of the road
and walk your bike across the street to use the walk light.

> 
> I dont want to start a rant, just wondering the law
> and where I can find out info like this.
> 

Another responder says he often goes on the walk light so that he can 
establish his position on the road.  The legal way of doing this (and 
what I generally recommend to people) is to queue up with traffic just 
like any other vehicle and stay in the middle of the lane until you are 
through the intersection.  Since you are moving as fast as the stopped
traffic there is no problem with slow speed laws etc.  Only once you are
safely a part of the traffic pattern should you move over to the right.

--jim