We (Sean, Colin & I) we’re recently asked to offer some good reasons for one to consider upgrading from SharePoint 2010 to SharePoint 2013. Here’s some of the goodness:

• Inline search – search and then filter in one go – BIG!
• OWA integration is huge – Word, Excel, PowerPoint, OneNote and PDF viewing (and editing, except for PDF) right in the browser – means iPad, etc. is a reality for using Office without installing it
• Cross browser support is much, much better
• Quick view is huge – a huge improvement over Datasheet view (works in all browsers, supports managed metadata, works all the time…)
• Mobile capabilities/view is improved – big improvement here
• Shredded storage – great for keeping DB sizes down
• Search with OWA (peeks) is great eye candy and useful at times
• Project Server (separate/$$) is SO tightly integrated.
• Work Management (a task is a task is a task… very cool/useful)
• Social – big improvements (or integrate Yammer…).  Being able to # and @ anywhere is useful if your users are up for it
• Business Intelligence – PowerPivot, etc.  Even sweeter/tighter with 2013 and SQL 2012 SP1
• Apps – lots of solutions added weekly that you can buy and integrate for a buck (and manage as IT – serviced a la carte)
• And for you Devs:
  i. HTML/Javascript oriented DEV

  ii. Windows Workflow Foundation 4

  iii. oAuth/oData, REST services

  iv. Client Side Rendering

  v. Remote Event Receivers

  vi. Machine Translation Service