The maximum number of friend requests you can send per day, as far as I can tell, is 100. I may be slightly off. Here’s the thing:
When you run out of friend-requests, it doesn’t tell you! So you can end up spending an hour (or hours) adding people without realizing you are accomplishing nothing! The way to tell is you refresh that user’s page, and it doesn’t say ‘friendship requested,’ or you just send the request twice and the second time, it will say the same thing it did the first time: “Do you want to make friends?” instead of “you already requested this person’s friendship” (or whatever the specific wording is, you get the point.)
Diclaimer: I may be blocked or something rather than just hitting a preset speed-bump. I did sent a lot of requests. I’ll know tonight at either Midnight somewhere in the US or in the UK.
Recently I found an awesome user group on Last.FM that had showcased one of my tracks as the “sound of the year…”
I know that back in the day, MySpace had a policy that allowed somewhere around 400 actions per day, that is to say, if you sent 400 friend requests, you wouldn’t be able to message anyone or anything…
LastFM doesn’t seem to have much trouble with unwanted spam. I have a few friends on Last.fm that spam me, but it’s all good spam (decent or great music to check out).
I’m basing my number, 100 on the fact that I got through two, fifty-user pages before the requests stopped working.
UPDATE: Two days later
After Midnight PST, was able to send 100 more friend requests.
But after Midnight the following night, I was only able to send around before they stopped working. I added a thread on Last.FM’s community/support forum here.
Maybe someone will shed some light on this. Search engine results for this problem are horrible.