Our allotment has a website, up dated by the association. I found it useful, pictures are updated and the allotment rules are on it. Some are a little odd, like you can't bring guns on site...useful to know one holder apparently brought a gun on site many yrs ago to shoot the rabbits... someone has driven a digger on site too, these aren't allowed for health and safety reasons plus we aren't insured for them
We also have a facebook page which all the plot holders can use. I've never been on it as I don't do facebook but I'm given to understand other plot holders go on it.
Facebook was seen as an open forum which everyone could join if they wished. Things like growing tips, recipe's, allotment news etc are posted...
The association still e-mail information to plot holders and we have two notice boards on site. One for association notices and the other for plot holders to put any thing related to allotmenteering on although the latter is seldom used.
There are 80 plots on our site and I think the association do their best to keep everyone in touch with each other and plot holders can choose which one they want to use or not as the case maybe.