For all the years I have been a PCB Designer, I've heard it a few different 
ways.

1) Put it close to VCC
2) Put it close to GND
3) put it in the middle of VCC  and GND
4) balance them evenly across the PC Board.

The only time I've seen a problem, was on a high speed design, that
was originally done by someone else (disclaimer)  where the
vcc line, and gnd line were .5" long and a .005 " line width.  The engineer
complained that when it switched from high to low, there was a bounce
in the signal. 

I think the best way is to make the connections as short as possible, and
as wide a trace as you can.  Bottom line is to make your engineer happy, 
they are the "customer".

Karl Bates
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