I expect it to get a lot of play in the media. In addition to being the seat of government, DC is the first place to vote for legalization on the East Coast.
Although the change has already been passed (overwhelmingly) by referendum, the city council still has to submit the changes to Congress, which will have 60 days to veto them. Further, at any point in the future they can restrict what DC can do via amendments to must-pass spending bills.
> DC is the first place to vote for legalization on the East Coast.
Well, DC is a city, and Portland, Maine actually already voted to legalize marijuana in 2013[0].
If DC were a state, it'd be the first state on the east coast, but it's not. It's the first city that is not part of a state (and therefore not subject to constitutional rights allowed states), which is what makes this case very interesting.
DC is tricky because it's such a special case, but remember that it's much easier to pass an initiative at the city level than at the state level.
Is it easier to pass an initiative in a city than in a state with a similar population? DC proper has a similar population to states like Wyoming and Vermont.
These are ballot initiatives that didn't go through the legislature. And for what it's worth, DC doesn't make it especially easy to get something on the ballot.
The initial steps (decriminalization, medical marijuana) were taken in the council though, and those set the stage.
Your question re:ballot initiatives interested me so I looked it up; signature-wise it takes 5% of DC voters distributed through 5/8 wards to get something on the ballot [0]. That's around 23,000 verified signatures. There are also the normal review periods/court challenges that are common in (nearly?) every state.
In Wyoming it's 15% of registered voters, nearly double DC, plus a fiscal review in addition to the normal court challenges.[1] I can't find anything saying direct initiatives are legal at all in Vermont, except constitutional amendments which come through the legislature [2].
In alaska (bigger but apropos since they legalized too) it takes about 30,000 signatures, and they have much stricter signature rules, including a house-district distribution rule. [3]
Overall it seems that DC is one of the easiest small 'states' to get something on the ballot in, although I have no way to compare how tough the court challenges are between states. Looking at the number of initiatives would be instructive but this comment is already getting long.