user1922,
We are having a discussion here, I apologize for any feeling of being brushed off as a freeloader. The forum has been "ddosed" by a guy named yuriygeorge and I think people are responding to you as if you are his clone.
Anyway, extensibility!
OK, so we know BTC can do payments, like paypal, just slower but without worry about transactions being reversed. Some like this others don't. Regardless if you want to change anything about bitcoin, well it is easier to just make it a new coin and that is exactly what has happened, litecoin, namecoin, 100+ others.
None of these coins can coexist with each other at the protocol level. Meaning they need different server daemons, different wallets, etc. Let's ignore the wasteful mining aspect, that is not what you asked. So I hope that explains how BTC is not extensible. Changing BTC creates a new altcoin. Now the more technical of you will probably point out that it is possible to update bitcoind globally and get new features added to bitcoin. To them I say, show me how you can get all the miners to agree to this short of a catastrophic bug.
Clear enough on BTC's shortcomings in this area?
Now for NXT, when it first was released, it had the payment ability. Faster than bitcoin so better, but essentially the same functionality.
In less than a month namecoin functionality was added. This immediately boosted market prices for NXT to around namecoin market cap. This is not simply because namecoin functionality is so good, it is because it showed the ability of NXT to do an update and gain a new functionality. Let's see any other altcoin or bitcoin do that.
the other thing it did was make clear that if there is a service, people will use it and spend NXT like drunken sailors. All the transaction fees then get distributed randomly to the lucky lottery winner of that block (approx minute). While the big NXT holders tend to win most lotteries, even very small holders eventually get some and this redistributes NXT, it also makes it a built in dividend reinvestment program, and makes NXT the only crypto that has a positive yield.
James