I don't know much about blogs, but yes, domain names can be very important, especially when trying to target keywords. I would suggest checking out Google AdWords Keyword tool or something similar to see what keywords get the most traffic. This is can be extra important if you're shooting for "big boob blondes" as I am sure that is a very competitive niche and you are going to need any help you can get. See what keywords are strong with searches and try to creatively work them into a domain name.
Check out the AdWords Keyword Tool al:
https://adwords.google.com/o/Targeti...=KEYWORD_IDEAS
Good luck!