I am still infant of microstock photography :-) Most of all I cooled down, it's going to be long an painful process. My first goal to have 100+ pictures on every site will take more than I expected. I could only reach this mark on SS and 123RF. Average approval rate is around 30% so I have to upload 500 photos to each site. How long it would take with site without FTP support or with daily limits :-)

Couple lessons learned:
1. Never upload full sized images. It's just to easy to get rejections. It's kind of difficult cause probably I have to resize photos to 1,2,3 and 4 megapixels for different sites.
2. Small batches. Even if there are no limits it seems that on most sites reviewer gets whole batch from one person instead of random photos which would be more fair.
3. Different subjects. Since I do not know what sells on particular website I put same batch on every one. My first was just a bunch of landscapes from my trip. Sometimes they are rejected for similarity.

102 pictures sold (101 on SS and 1 on 123RF). Some site got quite high acceptance rates but completely no sales. My best sellers is so far shot of lighthhouse, christmas ornaments, street shot from Manhattan, Crater Lake view and Machu Picchu shot. Landscapes are what I mostly do so it was probably majority of uploaded photos.

Rejected from SX, still waiting for approval at LO and SV.

My first goal was to sale 2 or 3 pictures just to say that I already sold my work once in my life Good luck!