Best way to receive comments is to comment comment comment.
In the beginning you have to write your comments into about 50 photoblogs per day, and do this every day on a regular basis. The most important thing is that your name is becoming known as an eager commenter. (use the same name over all the blogs of course ;-))
Second thing is to select the blogs where you are commenting.
If you are browsing a lot of blogs, watch out who is commenting there. You'll find names which show up again and again, those are the people who are willing to write comments and their blogs you should visit. Another important thing is to find "connections", finding out which people comment on people who left a comment.
There are some bloggers out here who receive a lot of comments just because they are so good and rarely comment themselves (examples: http://www.xoverip.info/pb/
But most of them receive comments from people where they left a comment themselves.
So don't watch out for blogs with much comments but for the commenters in those blogs and leave your note there.
Do this for a few months (!) and do it honestly, write more than a three words sentence and express your honest opinion.
This sounds like cheating? Yes, perhaps. I don't know. The game of give-and-receive-comments is a really strange system, and if you want to take part you have to follow the rules :-)
I did this for quite a long time last year and succeeded in receiving between 15 and 20 comments per image.
Then I had no time anymore for spending hours per day on commenting photos and the count of comments per image dropped to 3 or 4 per day which I receive without being very active as a commenter. But I found a few people I can almost call friends, who return to my blog from time to time and stay in contact by that (what is really worth more than 20 comments per day).