My husband calls me a Photoshop Diva  I'm good with it but not an expert by any means. It is such a powerful program that I learn something  every time I work on a new project.
I've recently been asked to check out an online photo editing application called Picnik and decide whether it would be easily used by amatuers with no photo editing experience.
My opinion is a very emphatic YES.
I wish i knew about this product a few months ago when i was out of town and realized that i had no photo editing software on my laptop. I didn't get any of the work done that I had taken with me.
This program has everything that a user needs to optimize an image with a super simple, bright and cheery,  learn as you go interface. ...and it's all online!
When applying the tools, the speed is as fast as desktop photo software. I uploaded a high res image and it loaded lightening fast for a photo this large! 
There is also a histogram for better control over brights and shadows. This is more for the advanced user but can be learned through the program by exploring the tool.
Features such as brightening, color correcting and saving the photo are simple to use and there are helpful notes that appear for each tool describing what each function will do. I was concerned when it came to saving the file.
Would a new user know what a .jpg file was and how to save it?. No worries. There is a slider bar that explains the outcome of each setting. Awesome!
The feature that I found to be useful to many and a huge timesaver is a  connection to most of the websites that you may want to display a photo ( flickr, facebook, myspace and more) through the interface!
Although I personally would keep using my more advanced software, I will definitly use  this Picnik for one particular feature that makes my job so much easier.
I have found the 'get from web site' feature unique and the perfect tool for me. You type in the URL of the page that you need graphics from and Picnik captures all of the graphics from the web page and displays them in the interface.
All that I have to do is click on the image that I need. This works great when a client has asked me to use their logos and I have to go in search of. Picnik lays it all out in front of me.
One thing I would like to see is a reminder for those capturing images from the web, to be sure that you have permission from the owner to use the image.
Picnik is a great tool for beginners and advanced users alike. It has most of the tools that you would need to easily enhance and share your photos.
I've just touched on the basics here but once you use Picnik you will discover the versitility in this program to help you create and share!