Changes 0.20.1:
New .agg() API for Series/DataFrame similar to the groupby-rolling-resample API窶冱, see here
Integration with the feather-format, including a new top-level pd.read_feather() and DataFrame.to_feather() method, see here.
The .ix indexer has been deprecated, see here
Panel has been deprecated, see here
Addition of an IntervalIndex and Interval scalar type, see here
Improved user API when grouping by index levels in .groupby(), see here
Improved support for UInt64 dtypes, see here
A new orient for JSON serialization, orient='table', that uses the Table Schema spec and that gives the possibility for a more interactive repr in the Jupyter Notebook, see here
Experimental support for exporting styled DataFrames (DataFrame.style) to Excel, see here
Window binary corr/cov operations now return a MultiIndexed DataFrame rather than a Panel, as Panel is now deprecated, see here
Support for S3 handling now uses s3fs, see here
Google BigQuery support now uses the pandas-gbq library, see here

(adam)