Simply, any coins are are Bitcoin forks, will fail. Anything noteworthy on an altcoin, like mini-blockchain, Bitcoin can/may incorporate in the future, leaving said altcoin in the dust.
Seconded - 99.9% of the "features" out there can be incorporated into Bitcoin's codebase in a heartbeat.
Stealth addresses from the genesis block on (an important privacy aspect) are one of the few things they can't do, not without a roll-over to a new genesis block with all outputs being reissued to stealth addresses computed from existing privkeys (read: practically impossible).
For everything else, there's
You two really think that Gavin et al are ever incorporating any major features that are found in an alt in to their 8 billion dollar baby?
If it's not something that solves a direct threat or major problem with Bitcoin I would put my money on 'never'. Or at least not in the next 5-10 years.
Everyone always says it would be easy to for Bitcoin to do xyz, but in reality even the simplest things are bogged down in politics.
That's not to say that the Bitcoin's devs aren't doing a great job at what they set out to do: Develop a stable codebase. Competing in the market as a product isn't how I think Bitcoin is run right now. That could change of course, but its not likely to for a long time if ever.
