I use mtgox because I don't trust any other entity with much of my funds. We've seen many exchanges come and go (bitcoin24,bitcoin7,tradehill,bitparking etc) but mtgox has been here all the time.
I see it the same. MtGox sucks, but at least they probably won't go away. Here is a relevant paper trying to quantify those risks:
http://lyle.smu.edu/~tylerm/fc13.pdfGox had 80% share back when that was made.