The fact that echo() can take several arguements is really a mute point.... take this for example:
PHP Code:
$var = "this";
// example 1
print $var . " is a string";
//example 2
echo $var, " is a string";
//example 3
echo $var . " is a string";
All three produce the exact same thing. print() may not be able to take several arguments, but who cares... both functions work with the dot (.) concat thingy.

Example 2 and 3 are exactly the same, even though 2 uses a comma and 3 uses a dot.