gistfile1.j

[[CPDate dateWithTimeIntervalSince1970:seconds] isEqualToDate:[CPDate dateWithTimeIntervalSince1970:seconds]]

// initWithTimeIntervalSince1970 is defined as
- (id)initWithTimeIntervalSince1970:(CPTimeInterval)seconds
{
    self = new Date(seconds * 1000);
    return self;
}

// equalToDate was defined as (not working)
- (BOOL)isEqualToDate:(CPDate)aDate
{
    if (!aDate)
        return NO;

    return self === aDate;
}

// equalToDate is now defined as (working)
- (BOOL)isEqualToDate:(CPDate)aDate
{
    if (!aDate)
        return NO;

    return !(self < aDate || self > aDate);
}

Why would you wonder that? Afaik, the valueOf method is implemented by all, as it is the way to get a primitive value out of objects. For instance: http://msdn.microsoft.com/en-us/library/ftx8swz5(v=VS.85).aspx, https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference/Objects/Object/valueOf etc.

I'm not wondering about browser implementation, more about if they will always return the same value for the same time. I've read several comments on Stackoverflow which said they were unsure about it.

If it's guaranteed to always be equal than the question is which of these two methods is faster. :)