Get satisfaction is $20 a month and Uservoice is $20……
The major difference between these two applications is that user voice allows your website visitors to suggest ways to improve your service or product and get satisfaction allows you to do the same thing plus three other things:
It lets your visitors ask you questions and answer each other’s questions about your product or service. It also lists the top support questions and their answers and tries to suggest answers to your question before you make your final submission. Also lets you report problems and give praise.
So user voice has a much narrower functionality… simply to let your website visitors make suggestions to you on how to improve things. And then allow your website visitors to vote on those suggestions. So you know, what is the most important to your visitors.
Get satisfaction lets you do the above plus provide and receive support.
Major plus for Uservoice: Has domain aliasing ( in $20 plan ) so that your info can have seo value under your own domain. This will require altering the CNAME record on your DNS. Are they indexed by google ? Can I insert ads on the pages? This is available in the Get Satisfaction service at the $89 a month rate. wow.
Are there any open source alternatives or anything cheaper?
http://www.opensourcerails.com/projects/1785-OpenMind : Nothing like uservoice
http://www.betaeasy.com/pricing-signup : clone of uservoice.
http://code.google.com/p/cnprog/ : A chinese app that uses uservoice for feedback. hmm.