Not quite sure what the "agreement" with Shutterstock is that is referenced in this article - perhaps the affiliate links?

I think so, they are offering Promo-Codes for both shutterstock and istock:

http://adscdn.flaticon.com/coupons/window?lang=english&sponsor=shutterstock
http://www.freepik.com/istock-promo-code

$15.84 here

My best selling vector had 12 dls on one day, usually it has 2-6.
My best selling photo has 2 dls/day on average, more in the second half of the year because it's a picture of cinnamon.
Highest number ever for one shot was 6 if I remember correctly

50% drop since Adobe!

Not that much, but about 25 - 30% down. October, however, best month since Adobe took over, but mostly from some ELs
On the other hand, October has always been the best month of the year.

So you want to upload to a site that pays $ 0.005 per DL?

Yes quite obviously he uses parts of other designers vectors. Other than that I wonder how he got that huge load of similar stuff accepted anyway. I even get a rejection when I try to upload a completely different illustration of the same subject. 

FT was #5 for me, for a long, long time. Now #2. Go ADOBE!!!

FT was my #2 since the istock debacle in 2011 - but when Adobe took over sales started to crumble, and it fell far behind istock again. Nowadays I have to rely on the constant growth at SS. Go Shutterstock!

The answer is in there link you posted. If a buyer doesn't want to credit the author right next to the icon, they have to buy a license. There's also a subscription scheme, look here:
https://thenounproject.com/handbook/royalties/#getting_paid

I saw this and it started me wondering:

Quote from: Cesar on May 29, 2015, 08:22

i have lower sales too, my rank drop from 600 to 850, my explanation was , my images are not popular anymore, my rank fall, so someone must sell more.

Supposing there are 40,000 contributors on FT, anyone under 1000 (the top 1000) is doing pretty good? Right or am I wrong?

Then I started thinking, is this rank that flexible and Cesar will jump up with a few sales more next month. There's a big pool of people with similar numbers, so rank can change 250 on a couple sales?

What does it take, if anyone can estimate, for someone to be a top 1000 on FT per month. How many sales or better question,  how many "Credits".

Not asking for anyone's personal finances, just the question, what's the edge of the top 1000?

Weekly rank can change by some hundreds - in a good week I'm in the 800s (earning about 200 credits/week), this (bad) week I'm at 1500 (below 100 credits/week).

Overall rank is far more interesting, highest I ever had was 267, now down to 342 - not only have I submitted less last year but also opted out of dpc - shortly after that I dropped from 270 to 300.

So, to answer your original question: A weekly rank of 1000 equates to an income of around 600 credits. Considering all posts in this thread, an overall rank of 1000 equates to an income of 150-250 credits

I've had some files deactivated for hilarious reasons, but this one tops them all (showing the file from FT, because on IS of course no longer visible):

Original description: Englischer Garten, Munich's largest park with the Monopteros temple on a hill

Deactivation reason "The content is not suitable for our broad Royalty Free license; the reason given was: This content is not suitable for the Royalty Free Licensing model. Please see: http://wiki.gettyimages.com/castles-in-europe/"

Besides that we have Freedom of Panorama in Germany I can't spot the castle in the image. Can you?

Shutter - a little lower than expected (usually March is the best month of the year) due to lack of ELs (only 2 compared to an average of 5)

Fotolia  - disappointing: down 15%

DT - slightly better, downward trend seems to be stopped

istock - surprisingly up 20%, but mainly due to 2 big ELs and PP, no change in regular DLs

veer - average

123 - disappointing: down 20%, a downward trend seems to establish

Pond5 - way below expectations, 2Dls in a month

Panther - still on a very low level, almost only subs

motsphotos - way down from previous months, almost only subs, too

Alamy - average, some DLs but not of high value

You have to remember that when you have a client commissioning they always get more demanding than you thought... and you end up investing much more time than if you were just doing something for stock.

It never fails for me...is like they want this and that...it sounds simple, straight forward, but then..things start to change, and you spend more time doing this and that...

I rarely have that problem with my clients (fortunately I can handpick them), and they wouldn't want to pay more. I earn the bigger money with other services they hire me for, like advertising and photography.