This slowing-down is a natural step in the development of a community anticipating its own purpose - that is, supporting a club which doesn't have a physical aspect yet. It would be unrealistic to expect even the more active posters to keep posting as often as they did in the first weeks. Keeping a community active like this isn't easy, and it partly involves a conscious effort on the part of the forum community ourselves to keep ourselves active. That said, there are a few things to consider:
- At the moment, this community is highly focused on the team and possible news about its future. That's great and all, but there's not much of a social aspect here. Many forums have an off-topic section which is more active than the on-topic areas. I know there have been efforts to start this - and I've made zero effort to encourage them, which is on me - but you could really try to push to get this section active. A social forum, with threads on "what are you listening to" (I know we have one of them), forum games, discussion about news, politics etc would not suffer from having to anticipate its purpose and can inspire a lot of debate, which engenders activity.
- Plan for the future. It's great having ideas like the "vote for our starting XI" thing but if you use up all your creativity straight away you will inevitably run out of steam. Consider launching one new thing like this per month or so will serve to keep the interest topped-up when it's flagging and will space out the creativity.
As regards the Starting XI vote, it's great but at present it's just a list of names, many of which farfetched. It's fun to dream of legendary signings, but it doesn't really translate to a team - we're picking a first XI of all DPs and a second XI of USMNT players ATM. If you, say, started by getting people to debate and then vote on what positions work best for DPs then you could follow up by a position-by-position vote knowing what calibre of players you are looking for in every spot.
Now that you've started the vote thing it's probably best to leave it, I was just using it as a hypothetical analysis. But still, you could consider doing something new like having one thread a week for 19 weeks, where you ask everyone to debate which two players (non-DP) they'd like to steal in the expansion draft, and hold a vote at the end of each week. Maybe another thread for asking people to suggest college players they've heard of. Etc etc.
- Following on from this point, exploit the heck out of any announcement the club does make. Start threads about them, start votes about them, start competitions about them. Do anything and everything to attract in new folk and excite those of us who are forum veterans. Also exploit the heck out of the World Cup, as it's going to create a lot of converts to football and many of them will be in NYC.
- Recruit. It's absolutely imperative to still be actively trying to expand our member base. There must be more than 150 people who are willing to join a forum for a new club, especially when half of them live outside the club's catchment area. Admittedly this isn't easy - when the club nears kickoff around the turn of the year, but you can only keep trying. Keep posting adverts on twitter (exploit the hashtags), try to get the official club twitter to give you some publicity - if they don't immediately reply then exploit their tendency to retweet pictures of people wearing the club shop - etc. Forge links with other groups - try to get some of the AO crowd here for example. Post comments on the club's Facebook page. Try to interact with Reyna, Pernetti and Kreis. Do anything and everything. Every time someone joins, their activity gives a half-dozen other posters a kick of activity in replying to them. With luck, the replies then get the new poster to respond. If you haven't had any new members for a while, potential recruits will sense it. It can be hard to get new members into a community where potential recruits feel the community is entrenched and hard to break into. Having a constant stream of new interest is important, as it emboldens other potential newbies.
- I'm sensing the twin trends among many US members of either being new to football, or new to the MLS. Have you considered a Primer guide, explaining how the MLS works, for instance? You could also have Q&A threads about football in general, where people new to the beautiful game can ask questions about how it works.