I distinguish between recieving criticism and recieving correction. This is normally dichotomized as criticism and constructive criticism. I suppose when you write a blogpost, and many other tasks, you are implicitly assuming you've made some number of mistakes. Recieving correction then doesn't tell you new information regarding your mistakes, and furthermore makes your blog closer to being correct. This is particularly true given how easy a spelling or grammar error is to correct once you know it's exact nature. I think the situation changes when the criticism pertains to some dimension in which you didn't know you were failing, and worse still when the necessary correction will take a great deal of effort or is simply not apparent. I don't think most people would enjoy recieving such a criticism, even as it eventually makes them a better person.
Concur. Whenever a reader points out an error in my blog — whether of fact or attribution or spelling or grammar or syntax or punctuation — I take the time to thank them and ask for more of the same. Why? It only makes my blog better. I love being corrected.