Push notifications in PHP using Amazon SNS/SQS?

On my site I'd like to do push notifications of comments like Stackoverflow does. Amazon SNS/SQS seems to provide a framework to do this but I'm having difficulty finding any code/explanation on the web for anything beyond a "hello world" equivalent.

From reading the AWS SNS/SQS documentation it looks like I need the following:

logic:

post comment/answer to a new question
create topic (for first comment/answer only)
publish message
subscribe to topic

PHP on the page where comments are posted (http://mysite.com/postCommentOrAnswer.php):

$comment=$_POST['comment']; //posted comment
require_once 'application/third_party/AWSSDKforPHP/sdk.class.php';
$sns = new AmazonSNS();

$response = $sns->create_topic('SO-like-question-12374940'); //create topic

$response = $sns->publish(
  'arn:aws:sns:us-east-1:9876543210:SO-like-question-12374940',
  $comment
);  //publish comment

$response = $sns->subscribe(
  'arn:aws:sns:us-east-1:9876543210:SO-like-question-12374940',
  'https ',
  'https://mysite.com/notificationsReceiver'
); // Subscribe to notifications

PHP on the page where notifications are received (http://mysite.com/notificationsReceiver.php):

no idea, thoughts?

Obviously, this is not close to being a complete demonstration and probably has some incorrect function calls but I was wondering if someone might be able to help build upon this?

Your comment implied that you are not wedded to SQS, so I am answering with a MySQL solution.

Unless you're dealing with so much traffic that messages would actually ever get queued, I'd recommend just a simple MySQL table approach.

I have a site with a MySQL notifications table that looks like this:

CREATE TABLE `notification` (
    `id` INT(11) NOT NULL AUTO_INCREMENT,
    `user_id` INT(11) NOT NULL,
    `notification_type` ENUM('inline','popup') NOT NULL DEFAULT 'inline',
    `html` TEXT NOT NULL,
    `entered_date` DATETIME NOT NULL,
    `display_date` DATETIME NOT NULL,
    `show_once` TINYINT(1) NOT NULL DEFAULT '0',
    `closable` TINYINT(1) NOT NULL DEFAULT '1',
    `destroy_on_close` TINYINT(1) NOT NULL DEFAULT '1',
    PRIMARY KEY (`id`),
    INDEX `user_id` (`user_id`)
)
COLLATE='utf8_general_ci'
ENGINE=MyISAM

This table is checked upon page load and the proper notification is displayed according to the notification data. Insertion is done as various actions or events occur on the website.

I'm at well over 10,000 users and so far this approach has not proven to be a bottleneck for the site. I don't expect it to anytime soon, either.