I don't know that "seeing" lag times and write speed is all that useful
in gauging the real-world performance of a digital camera. In 2003 I
took a series of a couple dozen photos of racing cars as they entered
the track, one after another. According to the EXIF data they were as
little as two seconds apart, averaging something right under three
seconds. I don't remember having to wait for the camera to prepare
itself. The buffer seemed to be emptying itself fast enough to accept
another image by the time I was ready to give it one.

That was "old" technology: Nikon Coolpix 5700. I reckon you could find
lag time and write speed data on that one. Whatever it is, one picture
every three seconds or so is about all you're going to be ready to take,
your own self.

Have a look at the difference in bulk between a CoolPix 8700 (close to
the same size as a CP5700) and a 20D Canon. Lotsa weight difference,
too.

Comparison of the 20D with 24-70 (38.4-112 equiv) and CP8700 with
35-280mm equivalent zoom range:

http://www.fototime.com/C898491FBD2A2CB/orig.jpg   front
http://www.fototime.com/A71907824F117BA/orig.jpg   top
http://www.fototime.com/4DED1BD0306F225/orig.jpg   rear
http://www.fototime.com/CBF8735023E6ED7/orig.jpg   Left

Stick one of the Ultra speed SD cards in the FZ20 and lag time
shouldn't be an issue.  Burst mode set to High Speed can capture jpg
images at 3 per second with a max of 4 or 7 images depending on the
image quality selected.  At Low Speed it can capture images at 2 per
second with a max of 4 or 7 images depending on the image quality
selected. When Burst Mode is set to Infinity it can capture images at
roughly two per second up to the capacity limit of the memory card.
Using a 512 meg SD card capturing JPG's in Fine mode, the capacity of
the card will be about 205 images.  You can also combine Panning Mode
with Burst mode if you are standing beside a bike trail or road and
want to take pictures of friends as they approach and bike past you.

I recently went down to the local airport to shoot jets landing. I captured a 737 wizzing
past at about 130 knotts. In burts mode I got about 12 frames with good focus. I use
the FZ20 with the Sandisk UltraII cards and never have to wait for the camera to write
before I am ready to take another shot.

Strange comment - see
http://www.dpreview.com/reviews/panasonicfz20/page4.asp and the extract
here:

"With write times averaging around 2.5 seconds for a 14MB TIFF the FZ20
is very fast indeed for a 'compact' digital camera - approximately
5700KB/s, and JPEGs - whatever the size or quality setting - are saved
in a second or under (most of this time will be taken up by the
processing). Very impressive stuff, and proof that the Venus II engine
is more than mere hype."