If so you might be interested in the public meeting on Wednesday March 2nd to discuss the options and what is planned for its reconstruction. There will be a site walk at 4pm and then a public information meeting at 6:30 PM at the MLK school at 100 Putnam ave, Cambridge. The info notice I got said the site walk was at 4pm, but others are telling me 4:30- if you plan on going you might want to contact Mass DOT directly to confirm. More information on the project here.
The good news is that they're planning on reducing the bridge to three auto lanes to make space for bike lanes each way. The bad news is that they're considering taking about 1' out of the sidewalks on each side.
Come suggest that the traffic lanes could remain 10' instead of 10'6" (they're 10" on the JFK street side of the bridge after all) and preserve the nice sidewalks that are often packed with pedestrians.
Narrower lanes aren't necessarily a bad thing, as they tends to calm traffic.
I hear some rumors about the City of Cambridge possibly creating a three lane/ bike lane corridor all the way into Harvard sq, which would be incredible. There's such a nice bike lane along much of North Harvard Street, which doesn't currently connect to Harvard sq, and there's such a demand for people coming from brighton and Allston into the square. Not finalized yet, but cross your fingers for the future.