商标LOGO问题请教

美国专利商标局对TM 和SM 与 ®区别的标准答案
如果你有兴趣可以在USPTO(美国专利商标局)的官方网站查询相关内容http://www.uspto.gov/smallbusiness/trademarks/faq.html)

What is the difference between the notations TM or SM and the ®?
Any time you claim rights in a mark, you may use the "TM" (trademark) or "SM" (service mark) designation to alert the public to your claim, regardless of whether you have filed an application with the USPTO. However, you may use the federal registration symbol "®" only after the USPTO actually registers a mark, and not while an application is pending. Also, you may use the registration symbol with the mark only on or in connection with the goods and/or services listed in the federal trademark registration.

个人观点如下:
® 是世界大多数国家认可的注册标记.® 在中国和美国均是注册商标标记.
TM是相对与SM(服务商标)而言的.
TM是美国法律的产物,在中国法律没有相关规定,更为准确的