During BWE3 I did not read this forum because I tried to spent most of the time ingame. On Saturday noon I couldn't wait anymore and founded a little guild, "The Temporarians [TEMP]". Until Sunday noon hexe and me had been alone there but then a small number of other GW1 Wolf Guard players joined. Despite that really, really small number we had been able to gather 500 "influence" over those two days enabling me to add "politics" to the build queue - around 45 minutes before the BWE ended, hihi. But that shows that even small guilds should be able to aquire a guild emblem in a couple of days. I'm not sure whether there will be guild capes, but there will be weapons and armor with guild emblems coming with later upgrades in politics.
Another information interesting to know is the fact that every character of an account can be in different guilds. In the guild dialog you can see all the guilds at least one of your characters is in. The only confusing issue is that your current character is listed in all that guilds and only a tiny gray bar over a tiny green square tells you, that your current character is not "representing" that guild yet.
Whenever a character joins a guild, whenever a character logs in each day and whenever a character completes an event on the world map (those hearts) the guild gets 10 influence - but only if the character is representing that guild. All that is not account-based but character-based. Within the very first days one can accumulate quite some influence points by simply logging in every day with several characters. Later on this gets less important I guess but at the very start this might be helpful to get the most basic upgrades for the guild, e.x. the emblem.