nothing serious? Tradehill decided to shut down because of banking troubles. What is not to say Mtgox would suffer the safe fate? If Mtgox, went down that would pretty much cause bitcoin price to crash.
Tradehill shutting down and Mt. Gox shutting down are two very different scenarios. Neither event kills Bitcoin but the latter would cause a total crash in price and Bitcoin adoption would take a huge step back. However there is absolutely no reason to assume that Mt. Gox is having any trouble. It's important to remember that Tradehill was an US exchange, what is common between Mt. Gox, Intersango and Cryptoxchange? None of them operate in the US.
Mt. Gox has been handling its regulation related issues very nicely and has not had any trouble with its most important bank accounts and it has even had functioning SEPA deposits for a good while now. Intersango has functioning SEPA both ways and they have basically solved the issues related to their UK account and as far as I know Cryptoxchange is also running a very solid business.
Remember that Tradehill was only slightly bigger than Intersango and Cryptoxchange, the difference was not huge. Mt. Gox is on a totally different level. I see a promising future for Intersango and Cryptoxchange though, they are providing a great service especially for European Bitcoin users for which Tradehill was a MUCH crappier exchange overall.
Tradehill was clearly a declining exchange and nobody lost money in this process thanks to the admirable business practices of Tradehill. I can actually think of a good number of ways to look at this whole situation from a "glass half full" perspective.
1) We are seeing the emergence of solid, ethical business practices. The way Tradehill handled everything is admirable.
2) Even though the 2nd biggest exchange in the Bitcoin economy shut down, it didn't really change anything. We have come a long way and there are plenty of good alternatives to choose from.
3) Paxum ending their support for Bitcoin can be seen from a positive light as well, it seems like banks might be starting to think of Bitcoin as a threat. That means we might be making the transition from nothing to something. From usability perspective this doesn't change anything, Paxum isn't very relevant in the big picture. It's just one payment processor.
4) Combined these events, just like the MyBitcoin scam and the Mt. Gox hack back in the day (although these were MUCH more severe events), will add pressure to innovate. MyBitcoin's demise lead to more robust wallets which are both convenient and much safer. Mt. Gox hack lead to Mt. Gox taking their security seriously and other major exchanges have don so as well, with Tradehill and Intersango having clear security records.
With the announcement of p2pool and its huge success, the only part in the whole Bitcoin equation that is still too centralized is the exchanges. I think these recent issues will add further pressure to develop convenient p2p exchanges and convenient services of real life exchanging. I believe all of this will lead to good things eventually.