Very sad... Things are getting worse and worse there. Now, with 80,000 photos added weekly it's a daunting task to keep the stable level of sales.
I wasn't uploading for 3 weeks and my income has decreased about 50%. Now I uploaded about 80 good quality stock pictures (here is a link: http://www.shutterstock.com/results.mhtml#gallery_id=64681&page=1) and there is almost no bigger rush noticable.
I don't want to make this post look like unproductive complaining but I am just a litte anxious and doubting whether any efforts make sense.

As a critique, they all have blown out white skies, except for the ones where you put in the fake blue gradient.  That may make them undesirable.  You have much nicer other stuff in your port.

April was bad for me as well, but good everywhere else. It's probably just a bump in the road. Or the buyers are going elsewhere because my sales numbers (overall) are still stable.

sjlocke - yeah, you are right I am still learning, however, I tried to make them looking like 'old-stock'. You know, I have seen plenty of stuff with clouded sky and people and they were great pictures for stock. But yes, I must have something wrong with mine.

Icefront -> it's interesting what you say. Can you develop a subject about new industry needs and changes ?

I had my best month ever in April.  I´m taking your dl´s 

I found many awful images at all microstock sites, even those that have "highest standards".

After adding 150 January-February and some in March, I had a big fat BME in March with On Demand and Extended too. No uploads the last 2 months made my sales collapse by 65% in April. Apparently, you still have to feed the beast, more and more.

SS in my experience is definitely one that needs to be continually fed in order to keep  steady earnings there.  I'm not producing a heck of alot of stock imagery these days (8-10 images/ week) and it seems like SS needs about 20 or so quality images/ week in order to maintain decent sales.

Yes, with a minimum of 10, with a wide variety. It's useless to upload a series since you just pinpoint the temporary attention then on one subject.

Perfect example of a point I've made many times before, this IMO is what could eventually lead to the demise of some microstock sites. When will sites learn to actually look at the image not just judge it on technical terms. And the problem is getting bigger every day because these sites seem to think they need to keep announcing how large their collection of images is, and yet what do they think a buyer would prefer - sorting through pages of cr*p like this or just being presented with one or two pages of good quality relevant results.

Yes, but even what you sad is 100 percent true the new sites which are trying to establish themselves on the market with a premier collection... well, they are not doing really well. I am afraid subscription sites always need a lot of new images... weekly. If one site has 50k a the other needs 60k... etc. No one on the Earth needs 50k or even 10k images a week. But the agencies aren't stupid. The customers are those who are choosing the one which is offering 'MORE'. It is is difficult to communicate that you have better quality while it is so easy to prove that more is MORE.