How do you think search engines will evolve in the next 5 years?

I think the following things will be revolutionized with Search engines

SEO :  It will have more check and balances to give more accurate result and better user experience to the search engine users.

PPC : Video Marketing and Banner advertising is going to revolutionized and based on the customer interest and re-marketing more personalized. Apple may start their  pay per click program just like google adwords and Bing Ads

Mobile App and Wearable

Search engine will not only index the Mobile Application data in their search result but also capture the data in smart devices( wearable) such as apple watches and Fit BIT

I personally think "syncing your personal data" and "cloud based" would be more part of the game here. That can also increase your brand value if you were a Public Figure or An Organization that needed more awareness. Could also be that Google Adverts will take it to the next level.How they do so will be a thing of the future but lot of technology involved definitely.

The search quality software is incorporating more and more NLP and machine learning to predict exactly what sources are most relevant and informative to a specific user, predicting the intent of the user.  Essentially, the algorithms are predicting exactly what the user wants to see, and then matching it to the best documents. In other words, the focus is moving away from statistics on document content to modeling what the user really wants to see and giving it to them.There's also a trend toward more contextualized search and special purpose search engines. For example, sites like Yelp or Hours of operation are essentially small, specialized search engines with only a narrowly defined focus.  I expect those business models are going to continue to proliferate, and contextual search may chip away at Google's market share, slightly. Following points are my another review of the same.

First, search engines will be available everywhere, not just on our phone, tablet or computer, we`ll be able to display images over any surface allowing us to have a bigger space so the context can be manipulated smoother, also, each search engine will understand and support touch, voice and keyboard interactions with the system, all at the same time; thus, while we are looking and arranging articles and editing them with our hands, we also be capable of telling the system to look for something else and display it juxtapose, creating two work "screens". Consequently, search engines will be a lot more interactive and integrated with programs such as word, excel, Photoshop, etc; indeed, not only facilitating search but letting people work and use them in order to create new content.

Second, as algorithms keep getting better and more personal information is embedded in the system, search engines will anticipate which information best describes and adequate our needs. The filters applied will depend on sources we prefer, authors we follow (social networks will be part of the system), meetings set in our calendars (let´s say you put some girls birthday: the search engine will display some days prior to the event, possible birthday gifts, clearly, depending on the other person interests (search results, face book biography, etc) and obviously taking into account your budget and all possible discounts among all sellers of the item.The last part of the foregoing paragraph is crucial, because we need search engines to help us perform our daily activities better and navigate easier through life, either physical or digital, but not in a passive manner (only reading) but to truly work with us side by side as if we were talking or working with a friend or coworker.

1. More accountability for SEO optimization providers
2. Tailored SEO services
3. Focus on behavioral rather than demographic SEO optimization

Search engines will be high smart to serve what you will never imagine and you will find yourself surrounded by results that you'd never think that anyone know it about you...