Is it bad design to hide a form's success message after a short time?

I was working on a non profit site www.gettingtoknowcancer.org and one of the requirements was to have a subscribe form on the right.So I created the subscribe form like this

which when clicked leads to this :

So when this form is submitted,the user is presented with a success message as given below

Now this "pop out" containing the success message recedes back into the launch trigger on the right after five seconds

So now the question is,is it bad design to hide the popup message after a short duration and if so,what are the alternatives.My concern was that I didnt want to place the onus on the user to hide it.

However considering the latter case that its not bad design, is there any research into the time frame for which short amounts of information must be displayed for it be read and understood by most people ?

I apologize for the large number of screenshots

Answer

OK design, but not necessary:

• It saves the user a click for dismissal, but if the user happens to miss the message, she might feel forced to re-open up the subscription form.


• 
  

  No matter the time frame chosen, there will probably be three groups of users:

  
  
  
  
  1. less experienced users that find it dissappearing too fast,
  
  
  2. target group users that find it dissapearing just perfectly when they are about to consider dismissing it,
  
  
  3. fast users that will want to dismiss it directly but finds nowhere to do that.
  
  
  
  
  


• I do not really understand why you put information about a Strategic picture in the box. If this is important, then it is contra-productive to automatically close the box.

Suggestion: Instead, make it easy to dismiss:

• Minimize the amount of text in the box, for example to: You are now subscribed!, to make it easy for the user to decide to close it.


• If you are going to send the subscriber an email with a confirmation link, then add the text Check your inbox! or similar to your popup box.


• Inform about the strategic picture some other way.


• 
  
  

  Make it easy to dismiss by:

  
  

  a. Adding a text "Click anywhere on this box to dissmiss" and implement that behaviour

  
  

  b. Adding a big closing cross image button.

  
  


• Don't close it automatically.

PS. The large number of screen shots are fine. They illustrate your question perfectly.