Trying to look to the future, without getting too far ahead of myself, I've been considering the exclusivity option at iStockPhoto. I haven't decided whether it's really the choice for me, especially since iStock only accounts for about 15% of my sales to date. But let's say I did want to go exclusive.
First thing I'd have to do would be cancel my accounts at all other agencies. At most of them, this is no big deal- just ask and they kill your account and remove your images. In fact, I did just this at Canstockphoto and Crestock. I'd had no sales to date at either, and decided that continuing to upload wasn't worth the effort. But at two sites it's not so simple:
At BigStockPhoto, you cannot remove a photo until it has been up for 90 days. This is supposedly to protect some sort of "investment" they made in their inspection of submitted images. (I don't think they inspected any of mine, they just clicked "approve all" - accepting something like 100 images all at once.) Whether I approve of this policy or not, I did agree to it when I signed up, so if I do ever want to go exclusive, I'll have to wait 90 days after my last submission to BSP.
At Dreamstime, it's worse. They lock their contributors in for 6 months! Again, I agreed so I'm stuck.
So, my advice:
1) Read those contributor agreements carefully. You never know what they might try to sneak in there. As someone new to microstock, you might be tempted to agree to more than you should, just to get things rolling. Don't. There's plenty of places that are more reasonable in their treatment of their contributors, so be selective.
2) Plan ahead. If you are locked in somewhere, and think you might want out some day soon, stop contributing! The lock-ins are rolling. If I upload a photo today to Dreamstime, for example, then I won't be able to leave until the end of Feb. 2010.
So, just in case I might want to go exclusive in half a year's time. Dreamstime and BSP have seen my last upload. Unfortunately, they lose and I lose, because of their overly restrictive agreement. Who knows, I might not even want to leave in Feb. I might LOVE being a contributor there. But I won't be, not under their current terms.