There have been always a debate on this matter.
The question is still unanswerable because WordPress blogs are increasing and so as the blogspot blogs.
Both are top platforms and are developing and advancing day by day
- WordPress fixes their bugs in every new version and blogger adds new features occasionally. Sometime ago WordPress was updated to version 3.5 and this made their blogs more secure and customizable.
- Again, Blogger added features like robots.txt, meta description, no-follow and no-index commands etc. to optimize blogs for search engines.