I stand corrected. II have only ever put plain text in my SEO fields, though so I guess ive never hit that issue. It’s worth mentioning that the Meta Tags plugin can help out a great deal with this, in combination with the trick above.
Just to clarify: value() returns the value of a field as string (does not convert kirbytags etc.); this field is used when we need a string representation rather than the page object itself. Using the above example you would get the following result: Some *text* and some (link: http://www.link.com icon: text: links) html() converts the field value to valid html, but does not convert kirbytags, either; so this field method is generally used with fields that do not contain kirbytext/markdown. Result would be the same as above in this case.