Most people who aren't risk-tolerant toward things like this are using services that instantly (or daily) convert to USD or EUR to minimize losses due to exchange rate flux.
It's really only a big deal for speculators, or people who are trying to run a btc-in-from-customers, btc-out-to-vendors business. SR is probably pretty interesting today.
Obviously, you can't. The intra-day prices have only been this volatile for 3 or 4 days out of 1000, though.
I think a half of one percent is pretty good for something that finally solved the centralization problem for digital currency and has only been really useful for a couple of years. It will, of course, continue to get better with time as the size of the market increases.
This big flux could well have been caused by a single old-school miner/collector dumping $1-2mm of BTC in one batch, too. Remember, these markets aren't really that big yet.
It's really only a big deal for speculators, or people who are trying to run a btc-in-from-customers, btc-out-to-vendors business. SR is probably pretty interesting today.