Version 26 is stable and version 27 (recommended) is beta with some minor changes. These versions work with both Arduino 1.0 and earlier Arduino versions. Read more on the visual micro site or visit the forum.

Summary of changes in Version 27

• Change: More efficient serial communications, with priority given to outgoing data
• Change: Serial "AutoScroll" works the same way as Visual Studio output windows by detecting mouse click or keystroke position. Set the text cursor to the end of the textbox to re-start autoscroll. Starts automatically in response to certain events such as PortOpen,Clear etc.
• Add: "Compiler Warnings" option. Switch on to see warning messages during compilations. For libs and core it is best used with compiler optimisation/caching switch off.
• Add: Serial "send" textbox changed to combobox with commands added to a type and search suggestions list. Most recent at the top.
• Fixed: Upload failed when the solution node was selected in the Solution Explorer
• New: A ".vmprogram" folder will appear under sketch folders. (more info to follow shortly)

Summary of changes until Version 26

• Fix: Serial monitor cursor
• Add: Serial monitor "Clear" checkbox. Auto clear serial data when the port is opened or when the checkbox is switched on
• Add: Echo serial to another port. Enables one or more serial ports to display data for debug then pass on to another port
• Add: Serial monitor optimized draw uses less cpu power when displaying inbound serial data. Displays at 5Hz from a buffer but still receives and echos at full speed.
• Change: Serial connect is now first in the row of checkboxes
• Fix: Nulls in serial data are now ignored.
• Fix: Invalid data after port open is avoided. Between one and three question marks sometimes showed when opening a serial port.
• Change: Serial "ReadTimeout" change from infinity to 100ms. Seems to improve the delays when opening vs forms and code when a fast running serial session ia active.
• Add: Try our best to auto detect when visual studio incorrectly sends a setup request which causes duplicate UI items. A small improvement to this annoying problem!
• Fix: Serial AutoScroll now works. Text is buffered when autoscroll is "Off" and flushed to screen when AutoScroll is switched back "On"
• Change: Visual Studio 2008 now uses the same microsoft "built in" icon, which seems better than having no icons at all. Existing users need to follow the /resetaddin guide to see the icons.
• Fix: Startup bug might have contributed to duplicate tool bar and menu item issues. Reminder: Read the /resetaddin guide if you encounter problems.
• Fix: Compile and intellisense errors caused by c++ class in a .pde/.ino and certain complex if statements
• Added: #define ARDUINO version to intellisense enabling newer arduino libs to show better intellisense in arduino 1.0 and older
• Fix: Library files and folders such as source control and .cpp extensions were not ignored (caused various issues)
• Fix: Adding libraries did not always add #includes into the master sketch file
• Fix: Adding libraries that already exist no longer causes duplicate #includes
• Mod: Serial monitor now uses fixed width font
• Mod: Serial monitor does not clear view data when opening and closing the port
• Add: Status bar messages during startup. Menu items such as libraries, if you have many, can take a while to load but do not prevent you using visual studio while they are loading. The status messages simply inform you that the addin is still loading and might not yet be showing the full arduino user interface.
• Fix: Output window was not activited for each build compile
• Mod: Setting the "Compiler>Configuration" option now prevents ALL arduino features and overrides in all configurations except for the specified configuration name. (Useful for arduino/windows simulation developers)