Sigh. It is trivial to look up the details on e-gold.
e-gold failed for one very simple reason: it did not register as an MSB, preferred a letter of the law approach ("gold is not money, therefore money regs do not apply") which convinced nobody. Not e-gold users, not criminals, not regulators.
That's why bitcoin exchanges should pay attention to the MT laws of their country.
This worries me a bit, about Mt. Gox:
To meet the definition of an MSB, a person must conduct more than $1,000 in business with one person in one or more transactions (in one category of activity listed above) on any one day. A business is an MSB for each activity for which it meets this threshold. However, there is one exception.
No activity threshold applies to the definition of money transmitter. A person that engages as a business in the transfer of funds is a money transmitter and an MSB, regardless of the amount of transfer activity. (see
http://www.fincen.gov/financial_institutions/msb/pdf/FinCENfactsheet.pdf )
I hope they are a registered MSB!