Hi Grafixer,
I went to your site and did not saw 150 * 150 px images but there is the image with 100 * 75 px on this link http://grafixer.biz/?page_id=6
If your thumbnail is generated 150 * 150 then go to dashboard -> setting -> media and check the thumbnail size.
View this screen shot http://awesomescreenshot.com/0a13tyyvba
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