Your cake is quite different from hers. As everyone else said you could say "inspired by" but this is your cake, you made it, so post it in your pictures. She should feel flattered not offended.
Jacqui
After looking at both, I'd leave it...You changed quite abit...
Ditto.....after seeing the pics it's clearly not the same cake, BY FAR....and I mean that in a good way! Both cakes are very pretty, but definitely different!
Is it copyrighted? Yes, no, I bet not. So even if it was the exact same she would have to obtain a copyright to sue you or anything. And because it is not the same and she has no copyright you are under no obligation to do anything. Personally you may give her name a mention, but then again whos to say the origninal cake wasnt a "copy" of something your competitor saw and changed a little?
Just my thoughts
~Alicia
You cake is beautiful and so is hers. Leave yours up. It's different enough from hers that it shouldn't be a problem. She might have come up with her design from someone else's work too. Who doesn't to some degree. When brides come to decorators with ideas they're getting them from somewhere. That's what inspiration is. She'll get over it.
I was being nice.
Oh, too cute. 
I honestly would leave it up. The cakes are similar, but you know, I think I've seen another one just like it here somewhere. While cakes are getting more and more creative, there are still some very basic ideas. Your bride had an idea of what she wanted. She brought it to you and you changed it. The cake you have is very much your work and is very much your own. It's a shame that there's an issue with a competitor, but can she lay claim to every three tiered square stack with ribbons around the side and a flower spray on top? At what point do you draw the line saying she can claim (a) and you can claim (b)? You made the cake, it's adorable and you deserve to post it. I'm honestly not trying to be ugly, but is she the original creator of this shoe on a cake idea?
I know you will do what you have to to keep peace, but don't let her anger steam roll you either.
I'll swear some people are just too full of themselves. I looked at her cakes and they look alot like the majority of cakes out there, nothing out of the ordinary, i'm sure she got ideas from other people. It would be a compliment, anyway, I definitely would leave it on your site, she should be flattered, don't feel bad, she's the one with a problem.
goodness, i would leave it on your website.
the bride brought you the photo and changed it to the way she wanted it. you did nothing wrong. if that was the case, none of us would do flowers, drapes, dots, swirls, etc. any of us could be told we copied, especially concider the plain white fondant cakes, havent we all done them?
Just a question...you're walking down the street and see someone wearing the exact same outfit as you, do you go up to them and demand that they take it off? Of course not, she'll think you're crazy! It doesn't matter who bought it first! She bought HERS and you bought YOURS.
Agree with Cathyscakes. And there was no cake on her website that sang out "Hey, I'm a 100% original" her ideas have been derived/inspired by other decorators too.
cakesondemand - you came up with a stunning variation of that cake and should post it proudly as others have said. It would be nice of you to mention whose design it was inspired by as well. If she is not happy with that then I think she is being unreasonable.
I may have an extreme opinion here (imagine that), but I'm not in the business, so that's my excuse. But on using the picture... does she credit where she got the idea of making a shoe? Does she credit who gave her the idea of putting ribbon around the edges? Does she credit who inspired her to stack? Obviously this is taking the matter to a base level, but the cake is yours, say it loud, say it proud.
I don't have any place on my site where I can post the inspriation from under my cake pictures. What proffessional site has that. I have business site that I just post my pictures for brides to view my work, are we supose to create our own styles and not use others there is so much out there besides when a bride brings a picture I don't know where its from and she may not either. That cake will be on my site but just not yet.
I just noticed that the web site of the competitor has been removed and I was wondering why? It does no harm to her except give her more hits on that web site.If that person is a member I wonder why they haven't come on to say anything.And I remember seeing that exact cake at another cake company!My husband works for a company that is constantly being copied, right down to the exact item, and they have checked to see if they can do anything.Well guess what, there's nothing that they can do to the 'competitor' unless they have the item patent.That is impossible to do for food items or nobody could eat!Remember that the design change has made it your own! 
I don't see her website either, can you pm me?
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