Apparently, for reasons as yet unknown, some Blogger users are finding that they are no longer indexed by Google.
Due to the generic nature of the code behind Blogger’s set templates, it appears that the ROBOTS NOINDEX,NOFOLLOW tag used if you’ve set your blog to private, is being inserted randomly into blogs that are most definitely not private, with the result that you will be excluded from Googles index.
The heads-up and solution to this problem came from the Marketing Pilgrim blog, and if you’re on Blogger, I strongly advise you to have a read, and then check your template, to correct it if necessary.
Of course, another solution would be to use a decent blogging platform instead….