New worksheet functions
Microsoft Excel 2013 Preview adds about fifty new worksheet functions for compatibility with the Open Document Format (ODF 1.2).
And you can now use web service functions (in the Web functions category) to anonymously access REST Web services. Of special note is the FILTERXML function, which lets you use XPath expressions to filter the XML returned by a WEBSERVICE function call.
Quick Analysis
Quick Analysis, as shown in Figure 3, is a new contextual UI tool that enables single-click access to data-analysis features, such as formulas, conditional formatting, Sparklines, tables, charts, and PivotTables. You can enable and disable the display of the new Quick Analysis feature in Excel 2013 Preview programmatically by using the Show andHide methods of the QuickAnalysis object.
Availability of new datasource
You can connect to a set of new data sources supported by PowerPivot, including OData feeds, Azure, SharePoint Data Feeds, and additional OLE DB providers. The newDataFeedConnection, ModelConnection, TextConnection, andWorksheetDataConnection objects contain data and functionality needed to connect to new data sources.
Using DataModel OM
A new DataModel object model (an addition to the existing Visual Basic for Applications object model) enables you to load and refresh data sources programmatically. This extension to the PowerPivot model introduced in Excel 2010 lets you integrate additional data sources and the ability to combined data from multiple data sources programmatically. Important new objects in this model include the Model,ModelChanges, ModelRelationship, and ModelTable objects.
Creating PivotTable and PivotChart Independently
You can use the decoupling of PivotCharts from PivotTables in Excel 2013 Preview. PivotCharts and PivotTables based on an OLAP or PowerPivot data source can be decoupled such that you can create a PivotChart independently of any PivotTable, and you can navigate through data by using a PivotChart-only experience. This is in contrast to the current paradigm where a PivotChart is created as a companion to a PivotTable. This decoupling is represented in both the Excel 2013 Preview Client and Microsoft Excel Services.
Single Document Interface
The change to a single-document interface (SDI) in Excel 2013 Preview has implications for programmability. SDI means that each workbook will have its own top-level app window and will have its own corresponding ribbon. All existing application-level window methods, events, and properties are unaffected by this change. All existing workbook-level window methods, events, and properties now operate on the top-level window for that workbook.
Turning animations turn on or off
You can use the new ShowAnimation property on the Application object to toggle the display of animations. Animations are disabled by default during macro execution. To enable animation, add Application.EnableMacroAnimation = True at the start of the macro. To allow Excel to show animations during macro execution, make this setting for each macro.
Timeline
Excel 2013 Preview includes a new Timeline control for filtering modeled data. Timeline offers a visual way to view and change a contiguous range of dates and filter pivot-based objects, such as PivotTables and PivotCharts. Timelines are related to slicers and extend existing slicer-related object model members. In addition, two new Timeline-specific objects are introduced: the TimelineState and TimelineViewState objects.
Source: Microsoft.com