When you share your web page on your Google+ profile or page stream, or in a Google+ community, you would expect the page title will be shown, together with a thumbnail image (if there is an image on the page), and the page URI.
Sometimes, however, something unexpected happens: Google+ is pulling something different as the title of your page. Why? It may have to do with the way you implemented schema.org mark-up on the page. Google+ currently looks for schema.org itemprop="name" and itemprop="image" first, and if it finds them regardless of type in the page source, then it uses them as the title and the thumbnail for the snippet of that page, as explained at Snippet — Google+ Platform — Google Developers (developers.
Perhaps in response to Using schema.org markup for organization (Google Webmaster Central Blog), in which Google announced that website owners can specify the logo for their sites, or an increased interest in appearing for search results influenced by location, many businesses and organizations are implementing Organization mark-up (or more specific types under Organization such as LocalBusiness) on their sites. For example, you may have written an article on your site, added <title>Article title</title>, even <meta property="og:title" content="Article title">, but you have also marked up your business in the footer section as follows:
<div itemscope itemtype="http://schema.org/Organization">
<span itemprop="name">Business name</span>
<span itemprop="description">Description of the business</span>
<img itemprop="logo" src="logo-location.png" alt="Business name logo">
<span itemprop="address" itemscope itemtype="http://schema.org/PostalAddress">
<span itemprop="streetAddress">123 Street</span>, <span itemprop="addressLocality">Town / City</span>, <span itemprop="addressRegion">County / State / Province</span>, <span itemprop="postalCode">Postal code</span>
You might expect Google+ to pull the Article title as the page’s title, because that is in <title> and og:title, but as mentioned above, Google+ first looks up for itemprop="name", and seeing that Business name is marked up as such, it will use Business name as the title of the page to be shared on Google+.
For Google to pick up Article title as the title, in the example above, you will need to mark Article title as itemprop="name" somewhere above <span itemprop="name">Business name</span> in the page source. This can be achieved, for example, by marking up the page with itemscope itemtype="http://schema.org/Article", using the Structured Data Markup Helper (www.
Not only is schema.org useful in controlling how your page appears on Google+ when it is shared, but also in terms of making your page more easily undestandable for major search engines, so it is worth familiarizing yourself with how schema.org works, even if it can take a while to grasp it.