Google is rolling out mobile site speed rankings. It’s a bit confusing. Slow sites will get penalized (unless they have really amazing content.) Medium to very fast sites won’t improve their rankings if they get faster. Slow sites will.
This only applies to mobile sites, which Google increasingly views as important. If your site doesn’t have a mobile theme or if it’s old and slow, you will now be at a disadvantage.
Mobile themes are used when a mobile browser like a cell phone is identified. The theme is optimized for mobile. Modern WordPress themes often include mobile themes. JetPack, a hugely popular plugin from WordPress, also has one. I use another plugin, WPTouch Pro, for mobile themes on several client’s sites.
Let me know if I can help with testing your website’s speed, speeding it up, or installing a mobile theme.
Only affects the slowest mobile sites.
Incremental improve to your site can make big impacts in speed.
Fast sites that go faster won’t see a ranking improvement.