I was recently asked for advice about a strapline- the “signature” that is often appended to a logo or other corporate messaging- and what SEO value it could provide.
My “I-only-understand-SEO-and-no-other-marketing-discipline” advice would be to use a strapline that soley describes the product portfolio or service being promoted. The problem is that this is likely be at odds with the marcomms requirement to provide a meaningful company “signature”. Sticking to that logic you could end up with useful search terms, but awful straplines. For example “JoeCorps- SEO and Internet Marketing” would be bearable but “USBs r Us- USB storage data backup mobile devices” is pretty grim.
I think that to get any possible SEO value from a strapline you’d have to compromise (or may be even ignore) the key message that you want to deliver.
Another issue is whether or not the search engines will be able to see the strapline’s words- sat in an image they aren’t strictly machine-readable so the engines won’t see them. They would only be useful if they appeared as plain text on a web page, and even then they would have limited SEO value unless it was used as link anchor text, for example.
Ultimately its best go for a strapline written for people and not influenced by how it might affect the search engines.