Whereas Block Explorer might be a useful tool, Bitcoin could survive without it.

Most important parts of the Bitcoin ecosystem, asides the main client that is, are the exchanges. They give the currency its value and without them, Bitcoin would become a fringe technology (no merchants would deal in it, as they couldn't pay their taxes with it.

Then we have the mining software and to a lesser degree the hardware (FPGA boards and the like). Should those be gone or less available it would be easier to launch a 51% attack on the network.

After that there are the mining pools. If they would disappear the miners would have a harder time earning a predictable wage. This dependancy has been mitigated with p2pool though, so the impact is smaller than it was earlier.

After that the services are less essential. Loosing the Bitcoin Forum, Wiki, SE, WeUseCoins or the like might make it harder for new people to get into Bitcoin, but wouldn't make it less functional.

Whereas Block Explorer might be a useful tool, Bitcoin could survive without it.

Most important parts of the Bitcoin ecosystem, asides the main client that is, are the exchanges. They give the currency its value and without them, Bitcoin would become a fringe technology (no merchants would deal in it, as they couldn't pay their taxes with it.

Then we have the mining software and to a lesser degree the hardware (FPGA boards and the like). Should those be gone or less available it would be easier to launch a 51% attack on the network.

After that there are the mining pools. If they would disappear the miners would have a harder time earning a predictable wage. This dependancy has been mitigated with P2Pool though, so the impact is smaller than it was earlier.

After that the services are less essential. Losing the Bitcoin Forum, Wiki, SE, WeUseCoins or the like might make it harder for new people to get into Bitcoin, but wouldn't make it less functional.