I just noticed this today. Please help me identify what's going on.

Maybe Bacterial Canker. Its very common on cherries in the Pacific Northwest.

Thanks Daisy,
My tree does look pretty wet around the gelatinous looking lumps. The tree has never been pruned, but we get strong temperature fluctuations throughout the year. This is the first year it is making a real crop too. I will look to getting a organic fungicide for it today. Then hopefully next year it and the plum tree will just needed painted with white latex to help protect them.

I would also check for borers. This article may help.

http://www.ipm.iastate.edu/ipm...

This article on bacterial canker may also be of interest:
http://extension.oregonstate.e...

Note that this latter is caused by a bacterium not a fungus, so a general fungicide wouldn't be helpful. Sometimes copper is recommended but the above article advises against it.

Thank you Sue,
Those links were very informative. I'll keep these in mind in trying to help it. I hope it can still be saved. The injuries are like hard smooth plastic to the touch.