Bitcoin is within 0.4% of its all-time high (http://www.coindesk.com/price/ - peaked at $1165.89 in 2013). ATH breakout could and probably is going to happen any minute now... In fact many exchanges have already reached their ATH in the previous hours.
This attack is applicable to SSL certs. Not most CAs as they have deployed counter-measures (such as using a long, random serial number) after the publication of the colliding MD5 rogue CA (https://www.win.tue.nl/hashclash/rogue-ca/) but I'm sure there are tons of companies with IT department and internal CAs who don't follow best practices and could be attacked with SHA1 collisions.
There are plenty of signals. Price is rising. Activity on Bitcoin forums is growing (r/Bitcoin users grew from 173,000 to 198,000 in a year, bitcointalk.org activity grew from 5900 posts/day to 6700 posts/day in a year, etc). Bitcoin remittance usage is growing (one example: http://bravenewcoin.com/news/bitcoin-remittances-20-percent-...). Bitcoin trading is increasing (especially in China, look at the volume starting in Q4 2015: https://bitcoinwisdom.com/markets/okcoin/btccny). More wallets are created (not a 100% "vanity" metric, but I agree the number of used or active wallets would be a better measure). More venture capital poured into Bitcoin year after year (https://news.bitcoin.com/venture-capital-all-time-high-new-r...). And more.
If a single metric was increasing this wouldn't be a reliable indicator. However all of the above are growing.
I am not sure there is any utility in differentiating between these 2 types of increased use. Either way it's increased use, and either way it's good for Bitcoin.
That guy shouldn't. But do you realize that this flaw exists in today's presidential election system?
If in the entire state of California, only 1 voter casts his ballot and the millions of other don't vote or can't vote, then this single ballot would decide all 55 electoral votes of California.
You can be sure that this vulnerability was probably discovered by some researcher, then sold to grey markets like https://www.zerodium.com or https://www.exodusintel.com/ (they pay up to $1 million for a highprofile iOS exploit), who then resold it to some government who is now trying to exploit this dude's phone...