What do you think? (the what do you think is here only because the link to the answer is too short of an SE answer :-/ )
Instead of asking if it should be converted to a comment because it's too short, you should be asking if it answers the question. If it answers the question, then it's an answer. While short answers tend to oftentimes hint that the post may not be an answer, length alone shouldn't be used to judge a post:
From How to Answer:
Read the question carefully. What, specifically, is the question asking for? Make sure your answer provides that – or a viable alternative. The answer can be “don’t do that”, but it should also include “try this instead”. Any answer that gets the asker going in the right direction is helpful, but do try to mention any limitations, assumptions or simplifications in your answer. Brevity is acceptable, but fuller explanations are better.
- emphasis is mine
Also, there's a lengthy comment thread below the answer. Before thinking about deleting/converting it, I'd opt for some edits first to put any additional, relevant information from the comments into the post. Editing is the most powerful moderation tool at a community's disposal, and it can turn poor answers into okay answers, and okay answers into great ones. ;) This also leads by example and teaches others how to write a good answer.
I went ahead and edited it to add the explanation from the comments to the post. Maybe someone else can edit it further, if need be. ;)
This opens for the one more request to stack exchange .Can we have a separate section at right corner where if some new content on developer.force.com blog is written same link appears on the right .May be say recent 10 blogs.This will allow readers to be update of the content available on developer.force.com.
Answering to the above i think that should be considered as answer as it points the right documentation