I think there is a very good reason for this on fluther – to prevent spamming and random chain mails like sending (hug) to everyone – I hated that on wis.dm.
It is not a function that I know of on Fluther. @Simone_De_Beauvoir has an excellent post on why it is likely not there. We rarely get PM spam here but if that was a function I am sure it would increase tenfold.
Yeah.. There’s no way to send multiple messages…
You have to go through and do it manually.
It generally takes about an hour if you send it to about 200 people.