A horrible, simply horrible hack to getting TweetNest to read JSON. Copy this to the /maintenance/ folder of your TweetNest installation.

loadtweetsfromjson.php

<?php
    // TWEET NEST
    // Load tweets (from JSON)

    error_reporting(E_ALL ^ E_NOTICE); ini_set("display_errors", true); // For easy debugging, this is not a production page
    @set_time_limit(0);

    require_once "mpreheader.php";
    $p = "";
    // The below is not important, so errors surpressed
    $f = @fopen("loadlog.txt", "a"); @fwrite($f, "Attempted load " . date("r") . "\n"); @fclose($f);

    $pageTitle = "Load tweets from JSON";
    require "mheader.php";

    // Identifying user
    if(!empty($_GET['userid']) && is_numeric($_GET['userid'])){
        $q = $db->query("SELECT * FROM `".DTP."tweetusers` WHERE `userid` = '" . $db->s($_GET['userid']) . "' LIMIT 1");
        if($db->numRows($q) > 0){
            $p = "user_id=" . preg_replace("/[^0-9]+/", "", $_GET['userid']);
        } else {
            dieout(l(bad("Please load the user first.")));
        }
    } else {
        if(!empty($_GET['screenname'])){
            $q = $db->query("SELECT * FROM `".DTP."tweetusers` WHERE `screenname` = '" . $db->s($_GET['screenname']) . "' LIMIT 1");
            if($db->numRows($q) > 0){
                $p = "screen_name=" . preg_replace("/[^0-9a-zA-Z_-]+/", "", $_GET['screenname']);
            } else {
                dieout(l(bad("Please load the user first.")));
            }
        }
    }

    // Define import routines
    function importTweets($data){
        global $twitterApi, $db, $config, $access, $search;
        $maxCount = 200;
        $tweets   = array();
        $sinceID  = 0;
        $maxID    = 0;

        echo l("Importing:\n");

        // Retrieve tweets
        if(is_array($data) && $data[0] === false){ dieout(l(bad("Error: " . $data[1] . "/" . $data[2]))); }
        echo l("<strong>" . ($data ? count($data) : 0) . "</strong> new tweets\n");
        echo l("<ul>");
        foreach($data as $tweet){
            echo l("<li>" . $tweet->id_str . " " . $tweet->created_at . "</li>\n");
            $tweets[] = $twitterApi->transformTweet($tweet);
            $maxID    = sprintf("%.0F", (float)((float)$tweet->id - 1));
        }
        echo l("</ul>");

        if(count($tweets) > 0){
            // Ascending sort, oldest first
            $tweets = array_reverse($tweets);
            echo l("<strong>All tweets collected. Reconnecting to DB...</strong>\n");
            $db->reconnect(); // Sometimes, DB connection times out during tweet loading. This is our counter-action
            echo l("Inserting into DB...\n");
            $error = false;
            foreach($tweets as $tweet){
                $q = $db->query($twitterApi->insertQuery($tweet));
                if(!$q){
                    dieout(l(bad("DATABASE ERROR: " . $db->error())));
                }
                $text = $tweet['text'];
                $te   = $tweet['extra'];
                if(is_string($te)){ $te = @unserialize($tweet['extra']); }
                if(is_array($te)){
                    // Because retweets might get cut off otherwise
                    $text = (array_key_exists("rt", $te) && !empty($te['rt']) && !empty($te['rt']['screenname']) && !empty($te['rt']['text']))
                        ? "RT @" . $te['rt']['screenname'] . ": " . $te['rt']['text']
                        : $tweet['text'];
                }
                $search->index($db->insertID(), $text);
            }
            echo !$error ? l(good("Done!\n")) : "";
        } else {
            echo l(bad("Nothing to insert.\n"));
        }
    }

    if((!empty($_FILES["uploaded_file"])) && ($_FILES["uploaded_file"]["error"] == 0)){
        $filename = basename($_FILES["uploaded_file"]["name"]);
        $ext = substr($filename, strrpos($filename, '.') + 1);
        if($ext == "json"){
            $json = file_get_contents($_FILES["uploaded_file"]["tmp_name"]);
            $data = json_decode($json);
            if($data){
                importTweets($data);
            } else {
                dieout(l(bad("Whoops! That's not valid JSON.")));
            }
        } else {
            dieout(l(bad("Whoops! That's not a JSON file." . $ext)));
        }
    } else {
        // Our form
        echo l("
            <form enctype=\"multipart/form-data\" action=\"loadtweetsfromjson.php\" method=\"post\">
                Choose a file to upload: <input name=\"uploaded_file\" type=\"file\" /> <input type=\"submit\" value=\"Upload\" />
            </form>");
    }

    require "mfooter.php";