Before 3.5, it was easiliy possible to select all cells of an inserted (empty) column (between data containing columns) by 
1) selecting the first cell of the empty column, 
2) extending selection to a neigbouring cell (containing data) by pressing SHIFT+ArrowLeft 
3) pressing CTRL+SHIFT+ArrowDown to extend selection until bottom of data range and finally 
4) reducing selection to the empty column with SHIFT+ArrowRight

This could be effectively done with only four keystrokes:
1) Hold down SHIFT
2) press ArrowLeft once (and keep holding SHIFT key)
3) press CTRL+ArrowDown once (but still keep holding SHIFT)
4) while SHIFT is still held, press ArrowRight

Now, at least in 3.5beta2, extending selection does not more stop at the end of the data range in step 3 but encompasses the whole (empty) column. 

Seems like extending a selection takes the origin of the extension as starting point instead of the actual cell.

Platform: Linux/RPM i686

Note: Possibly Bug#42535 describes a related phenomenon