diff --git a/HISTORY.rst b/HISTORY.rst
index ca81838c..a275d21b 100644
--- a/HISTORY.rst
+++ b/HISTORY.rst
@@ -1,6 +1,12 @@
 Release History
 ===============
 
+0.10.2 (2015-01-06)
+-------------------
+
+* Fixed an issue with ``--json-output`` (`issue #42 <https://github.com/ivankravets/platformio/issues/42>`_)
+* Fixed an exception during `platformio upgrade <http://docs.platformio.org/en/latest/userguide/cmd_upgrade.html>`__ under Windows OS (`issue #45 <https://github.com/ivankravets/platformio/issues/45>`_)
+
 0.10.1 (2015-01-02)
 -------------------
 
diff --git a/docs/platforms/atmelavr.rst b/docs/platforms/atmelavr.rst
index 9b8aa94d..9e9722d9 100644
--- a/docs/platforms/atmelavr.rst
+++ b/docs/platforms/atmelavr.rst
@@ -250,6 +250,11 @@ Engduino
       - 32 Kb
       - 2.5 Kb
 
+.. note::
+    If you are going to use onboard sensors, please install
+    `Engduino library <http://platformio.org/#!/lib/show/123/EngduinoV3>`_
+    with the examples.
+
 More detailed information you can find here
 `Engduino Site <http://www.engduino.org>`_.
 
diff --git a/platformio/__init__.py b/platformio/__init__.py
index 6fdb367f..f55145c6 100644
--- a/platformio/__init__.py
+++ b/platformio/__init__.py
@@ -1,7 +1,7 @@
 # Copyright (C) Ivan Kravets <me@ikravets.com>
 # See LICENSE for details.
 
-VERSION = (0, 10, 1)
+VERSION = (0, 10, 2)
 __version__ = ".".join([str(s) for s in VERSION])
 
 __title__ = "platformio"
diff --git a/platformio/commands/lib.py b/platformio/commands/lib.py
index f3b87445..96b750e5 100644
--- a/platformio/commands/lib.py
+++ b/platformio/commands/lib.py
@@ -1,12 +1,15 @@
 # Copyright (C) Ivan Kravets <me@ikravets.com>
 # See LICENSE for details.
 
+import json
+
 import click
 
 from platformio import app, exception
 from platformio.libmanager import LibraryManager
 from platformio.util import get_api_result, get_lib_dir
 
+
 LIBLIST_TPL = ("[{id:^14}] {name:<25} {compatibility:<30} "
                "\"{authornames}\": {description}")
 
@@ -160,7 +163,7 @@ def lib_list(json_output):
     items = lm.get_installed().values()
 
     if json_output:
-        click.echo(items)
+        click.echo(json.dumps(items))
         return
 
     if not items:
diff --git a/platformio/commands/list.py b/platformio/commands/list.py
index 3520d2ad..c47a95b8 100644
--- a/platformio/commands/list.py
+++ b/platformio/commands/list.py
@@ -1,6 +1,8 @@
 # Copyright (C) Ivan Kravets <me@ikravets.com>
 # See LICENSE for details.
 
+import json
+
 import click
 
 from platformio.platforms.base import PlatformFactory
@@ -23,7 +25,7 @@ def cli(json_output):
         })
 
     if json_output:
-        click.echo(data)
+        click.echo(json.dumps(data))
     else:
         for item in data:
             click.echo("{name:<20} with packages: {pkgs}".format(
diff --git a/platformio/commands/serialports.py b/platformio/commands/serialports.py
index d62d9482..c52f27da 100644
--- a/platformio/commands/serialports.py
+++ b/platformio/commands/serialports.py
@@ -1,6 +1,7 @@
 # Copyright (C) Ivan Kravets <me@ikravets.com>
 # See LICENSE for details.
 
+import json
 import sys
 
 import click
@@ -19,7 +20,7 @@ def cli():
 def serialports_list(json_output):
 
     if json_output:
-        click.echo(get_serialports())
+        click.echo(json.dumps(get_serialports()))
         return
 
     for item in get_serialports():
diff --git a/platformio/commands/upgrade.py b/platformio/commands/upgrade.py
index 212744a6..75172ccf 100644
--- a/platformio/commands/upgrade.py
+++ b/platformio/commands/upgrade.py
@@ -23,9 +23,19 @@ def cli():
             "newest version available." % __version__, fg="green"
         )
     else:
-        result = exec_command(["pip", "install", "--upgrade", "platformio"])
-        click.secho(result['out'], fg="green")
-        click.secho(result['err'], fg="red")
+        click.secho("Please wait while upgrading PlatformIO ...",
+                    fg="yellow")
+
+        pip_result = exec_command(["pip", "install", "--upgrade",
+                                   "platformio"])
+        pio_result = exec_command(["platformio", "--version"])
+
+        if last in pio_result['out'].strip():
+            click.secho("PlatformIO has been successfully upgraded to %s" %
+                        last, fg="green")
+        else:
+            click.secho(pip_result['out'], fg="green")
+            click.secho(pip_result['err'], fg="red")
 
 
 def get_latest_version():