Cracking at the spoke holes can happen to almost any rim....In fact its one of those things that you should look at a few times a year when cleaning the bike. (cleaning the bike
)
Some rims are more notorious for this problem than others. Note that Mavic renamed the venerable MA3 rim and came out with a whopping big warranty offer this year (they also tweaked the design slightly to prevent the problem)
Rider weight may be a contributing factor but most rims wear out eventually by cracking at the spoke holes or by using up the brake track on the side of the rim.