jeepj,
I believe I have only used it once. Here is some code that does not use a continue block:

my $counter = 0;
while ($counter < $limit) {
    my $item = shift @work_queue;
    my $thingy = some_function($item);
    if ($thingy ne 'PARTY') {
        ++$counter;
        next;
    }
    # more code if $thingy ne 'PARTY'
    ++$counter; # thanks ikegami
}
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Here is the same code with the continue block

my $counter = 0;
while ($counter < $limit) {
    my $item = shift @work_queue;
    my $thingy = some_function($item);
    next if $thingy ne 'PARTY';
    # more code if $thingy ne 'PARTY'
}
continue { ++$counter; }
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Here is my general rule of thumb for when to use continue

• You have 1 or more statements that need to be executed every single loop
• You have more than one possible short-circuit condition in the loop

It is a nice way of code re-use. Instead of doing

if ($condition1) {
    # statement 1
    # statement 2
    # statement 3
    next;
}
# more code
if ($condition2) {
    # statement 1
    # statement 2
    # statement 3
    next;
}
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You can just do

next if $condition1;
# more code
next if $condition2;
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