Trading and mining doge is great. But I don't know if doge can sustain it's growth.
Do you think Doge will hit over 200 satoshi again?
I do, although it can take a while. Things still need to settle. Dogecoin is the only one that can cater to the "general public" who happens to know what doge even means.
I'm not so sure about that. I grabbed some doge and I intend to keep them, although if I should be honest I would say there's a 10% probability dogecoin survives a year or two. I was not an early adopter of bitcoin, got my coins a year ago. So in case doge lasts for many years, could be cool to own some old doge.
But realistically speaking, I think even litecoin is pretty useless, I mean, what does it put on the table that bitcoin doesn't? It doesn't even leverage scrypt's advantages (acording to scrypt's creator).
Litecoin's only advantage that I know of is faster transactions. Same with WDC.
Bitcoin just can't be used for day to day transactions; it takes too long. The 30-50m blocks would be killer if you're sitting around waiting on confirmations at a store.
Hoping not to fork the discussion too much... BTC block size was not picked randomly. I apologize for not posting the source, but I recall previous discussions on this forum where people explain how faster block times basically translate into weaker validations. There's no free lunch there just by tweaking some parameters.
AFAIK, litecoin doesn't attempt to introduce any innovation to the concept beyond using a different hash function and tweaking some parameters. Other coins did try to experiment by adding new ideas to the mix: proof of stake for example.
As for bitcoin not being suited for practical day to day transactions, I believe some services can be built on top of bitcoin to mitigate that and offer fast transaction times. It is not realistic to think that 5-10 years for now we will still using bitcoin in such a low level fashion as we do now.
Back on the dogecoin topic, looks like dogecoin is the first altcoin with a lightweight client:
http://www.reddit.com/r/dogecoin/comments/1xdr4u/multidoge_010_released_light_wallet_client_for/pretty impressive, considering most coins consist of a thread here on bitcointalk.