Python version of https://gist.github.com/3773519 that pulls all bookmarks on the first sync, and does incremental updates afterwards. Also uses the Mac OS X keychain to retrieve your password so it doesn't need to live in a file on your computer in plain text.

allpinboard.py

#!/usr/bin/env python

"""
This script is designed to generate a simple html file with _all_ of your Pinboard.in bookmarks
The HTML file can be added to Launchbar's index as a custom bookmark file and you can search
your entire Pinboard.in collection instantly from Launchbar (by title only). It includes
any applied tags as part of the title to aid in searching.

Requirements:

* pytz
* requests
* dateutil

You should edit the username, bookmark_filename, and local_timezone variables
to suit your preferences.
"""

from datetime import datetime
import subprocess
import os
import cgi

import pytz
import requests
from dateutil import parser as date_parser

keychain_process = subprocess.Popen(["security", "find-internet-password", "-s", "pinboard.in", "-w"], stdout=subprocess.PIPE)
trim_newlines = subprocess.Popen(["tr", "-d", "'\n'"], stdin=keychain_process.stdout, stdout=subprocess.PIPE)
keychain_process.stdout.close()
password, _ = trim_newlines.communicate()

username = "dlo"
bookmark_format = u"""<a href="{href}" title="{extended}">{description}</a>\n"""
bookmark_filename = "/Users/dan/Dropbox/PinboardBookmarks.html"
local_timezone = "America/Los_Angeles"
basic_auth = (username, password)

url = None
try:
    timestamp = os.stat(bookmark_filename).st_mtime
except OSError:
    url = "https://api.pinboard.in/v1/posts/all?format=json"
else:
    last_modified_local_time = datetime.fromtimestamp(timestamp, pytz.timezone(local_timezone))
    last_modified = last_modified_local_time.astimezone(pytz.timezone("UTC"))

    # Check if bookmarks have been updated remotely since last local update
    response = requests.get("https://api.pinboard.in/v1/posts/update?format=json", auth=basic_auth)
    last_modified_on_server = date_parser.parse(response.json()['update_time'])

    if last_modified_on_server > last_modified:
        url = "https://api.pinboard.in/v1/posts/all?format=json&fromdt={}".format(last_modified.strftime("%FT%TZ"))
finally:
    if url is not None:
        response = requests.get(url, auth=basic_auth)
        with open(bookmark_filename, 'a+') as bookmark_file:
            for bookmark in response.json():
                bookmark['description'] = cgi.escape(bookmark['description'], quote=True).replace("\n", " ")
                bookmark['extended'] = cgi.escape(bookmark['extended'], quote=True).replace("\n", " ")
                bookmark_file.write(bookmark_format.format(**bookmark).encode("utf-8"))