Yahoo!® drops "®". Is "!" next?

Old Yahoo! logo 
New Yahoo! CEO Marisa Mayer has attracted a good deal of attention since her appointment as the youngest chief executive of a Fortune 500 company in July last.
Mayer's intends to restore Yahoo!'s stature as a technological innovator and has already brought about some changes in the organisation of the internet corporation.
Besides the idea of providing every employee with a new smartphone, Mayer has in fact decided to change something also in the Yahoo! brand, which was launched back in 1995.
As reported by The Huffington Post, the CEO has thught of getting rid of the ® symbol after 'Yahoo!'. This has been part of the brand since the very beginning. 
Posting an image of one of the lost ®s on Instagram, Mayer said: 
"One of our new Yahoo!s Andrew was really bugged by the registered trademark symbol at the end of our logo; he's gone on a mission removing all the R's from our site and our campus. This is one on the random R's we pulled off a wall :)".
The photo published on Instagram
Later on, she added on Twitter:
"Legal assures us that our trademark is implied and quite secure :)".
TechCrunch suspects that this decision was based on the consideration that at the moment it is difficult to find a successful internet company with a ® tacked on to its logo. Hence, also the days of the characteristic exclamation mark which follows the word "Yahoo" may be numbered.
This blogger ventures to say that this could be because:
1) the use of punctuation is a peculiarly human approach. For instance, until very recently Google ignored all punctuation symbols when indexing pages. It is just since late 2011 that Google has started indexing seven punctuation marks (%, $, \, ., #, +). The exclamation mark remains among the non-indexed symbols.
2) the domain name is www.yahoo.com.
While Yahoo! is dropping its ®,
Bernie is committed to drop 
½ pound

In any case, the story of the exclamation mark in the "Yahoo!" logo is quite interesting. As reported by Wikipedia, Yahoo! founders Jerry Yang and David Filo could not register "Yahoo" as the corporation's trademark, because there were already "Yahoo" trademarks registered with the US Patent and Trademark Office (USPTO). This is why they decided to add the exclamation mark to the word "Yahoo". 
Going back to the now missing ® symbol after "Yahoo!", it is worth recalling that §1111 of the US Lanham (Trademark) Act provides that:
Notwithstanding the provisions of section 22 hereof [15 USC 1072], a registrant of a mark registered in the Patent Office, may give notice that his mark is registered by displaying with the mark the words "Registered in U. S. Patent and Trademark Office" or "Reg. U.S. Pat. & Tm. Off." or the letter R enclosed within a circle, thus (R); and in any suit for infringement under this Act by such a registrant failing to give such notice of registration, no profits and no damages shall be recovered under the provisions of this Act unless the defendant had actual notice of the registration.
It is apparent that the ® symbol is not completely meaningless. It is actually relevant to the innocent infringement defence. Whilst failing to provide notice of a US registered trademark is not a defence to infringement, it may nonetheless limit or eliminate the damages available to a plaintiff and is relevant also to the theme of injunctions going forward forcing the defendant to stop using the trademark.