Heh, the people who benefit the most are those who jump in early as the value of the currency grows only when the currency becomes popular. Imagine if you were "Satoshi" himself/herself; how much money do you think s/he made off the Bitcoin popularity?
I see the emergence of all these side cryto currencies as an attempt for their respective developers to get rich a la Ponzi scheme.
Agreed. This has always been the drawback of crypto-currencies - they act (and people treat them) more like rare postage stamps than actual money, which encourages hoarding & volatile price swings. They're primarily a novelty which has avoided one extreme (inflationary bias by issuing too much money) by wildly swinging to the other extreme (strong deflationary bias = too scarce to function as proper currency and ends up with wild illiqudity based price swings). People seem to be backing "bitcoins" out of reactionary opposition to the way the Federal Reserve has devalued the $ to bail out the banks. That's fair enough as a belief by itself, but currencies need 3 things to sucessfully function - value, liquidity & trading stability (no short-term price swings as a medium of exchange) - and not just the first one. Unlike precious metals, etc, they have no more intrinsic value than fiat paper currencies.
Real currencies need a minimum amount of liquidity to function as currencies. A currency with a maximum 21m units isn't going to replace any national currency with a population of tens or hundreds of millions let alone a global 7bn. That for the USA alone would be like the Federal Reserve issuing only enough USD units in circulation for each American to have $0.07 each, it might be "valuable" as a fringe speculative investment (relative to holding other currencies like the Euro), but internally most Americans would end up bartering for nearly everything made in America due to a permanent currency shortage (made worse by a deflationary bias, ie, as time goes on it gets more difficult to acquire money - which is great if the world's population is shrinking, but the exact opposite of what you need when it continues to grow)...
Likewise with stability, short-term (<5 year) value changes cause a collapse in confidence. You see this regularly in 3rd world countries where the price of food doubles in a month results in "Dollarisation" (ditching the local currency in favor of $ or €

. Bitcoin's $9 to +$1,000 in 4 years is not price-stable enough. It's the deflationary equivalent of +220% annual year-on-year price inflation which far exceeds even the worst $ devaluation by a +20x factor.
It's value also recently crashed from $900 to just $460 in 48 hours.
Example : If you own a business buying say $100 widgets in bitcoins and selling them on for $130 equivalent in bitcoins, you'd have just made a massive loss paying out 217 bitcoins to acquire 1,000x widgets from a wholesaler only to be forced to sell all 1,000x 48 hours later for just 144 bitcoins with such a wild adverse currency movement spikes. In reality, most firms facing such a massive loss on the wrong end of such a spike wouldn't make the trade - they'd just close their doors to Bitcoins for the day... Earlier in the year many did just that when the "currency" hit an intraday high of $266 on a Wednesday, promptly collapsed to $105, rebounded to $180, then collapsed again to $120, etc...
Here's a July 2010 to Nov 2013 chart of "bitcoin vs gold":-
That's not what any currency looks like (except maybe Zimbabwe's inverse hyper-inflation chart

), that's what a 1990's dot-com bubble looked like after a huge amount of media hype, but just before the "pop"... (NB: Chart is
vs Gold not the USD).
The popularity of Bitcoin also means it's inevitable you'll get scammers creating a string of new crypto-currencies (benefiting from being an early adopter) with the same tactics that drive penny stock "pump and dump" / MLM scams (where the first guy wins, the second & third lesser so, and by the time the 4th & 5th guys come along, the 1st guy quietly cashes out, etc) but on a longer time-frame. Time will tell how many of these string of Bitcoin 2.0's are serious or just someone cashing in on a craze. Right now, Bitcoin's are mostly popular amongst geeks who understand the "what", but not "why" there's a lot more to currencies than just Forex rates vs the USD alone).