I have a 3 month old emd.co.uk In bing the domain is ranking #1 already and in top 5 for some other keywords. When it comes to Google.co.uk, the highest ranking I have is #55. I'm planning on doing a private blog network blast. My question is should I particularly look for a private blog network that has .co.uk domain extensions or does the regular .com sites are ok to use? Has anyone have any experience in the above? ie. managed to rank a different country level TLD site using just .coms?