I kept hearing that Serval cats in the wild (east Africa) are able to jump
"10 to 15 feet straight up" to snatch a flying bird, and I thought, How can
this be?  Are they making it up?

And then I saw this video - FF to minute 2:25 and see for yourself!

As for scale, this is probably about a 25-30 pound cat, that stands up to 17"
tall to the shoulders.  So he's larger than most domestic cats, but smaller
than a bobcat or cougar, for example.  Servals are cross-bred with domestic
cats to get Savannah cats.  Ashera are part African Serval, part Asian
leopard and part American house cat, and in their first generation from the
wild are the most expensive to purchase, ranging from $20,000 to $28,000
for one Ashera kitten.  They call the first generation F1.   Second gen. is F2, etc.

Video of San Diego Zoo show "Jumping Servals"

These are different from Asian leopard cats, which are smaller, and much
more common, for they have a wider habitat from India to western China.  
Asian leopard cats are cross bred with domestic cats to form Bengal cats,
which are considered semi-domesticated and often exhibit traits that seem
like they are reverting to their wild instincts.  

In case you may be interested in having a Bengal cat, watch this video
first:  .

- part 1 of
a 3-part series.  The commentator is actually enjoyable!

........ approaching 2 million views! 3-1/2 years online.

Serval cat + domestic cat = Savannah cat

Asian leopard cat + domestic cat = Bengal cat

Serval cat + Asian leopard cat + American house cat = Ashera cat

It looks like Savannah + Bengal = Ashera too, but nobody's saying that.