I have been debating on purchasing a domain with a .org because .com is taken.
Do you think it is just as good for seo and worldwide purposes?
Google treats all TLD the same way for ranking purposes. If a .net had better content and backlinks than a similar named .com site, it would likely rank higher. Google is more focused on other factors than just the TLD aspect. With that being said, the consumer or person visiting your site might prefer to visit one that has .com as the TLD if that is what they are more familiar with.
From my experience Google tends to weigh .net and .org about the same as .com TLD