This is our first post-Open Source release and includes our first fixes and features contributed by the community.  In addition, there are a number of enhancements done by the NETMF team here at Microsoft and there are new processors available from a new partner.

Here is the list of feature changes:

1) VS2010 compatibility, with support for C# express as before.

2) Multi-targeting support for VS2010: from .NET MF 4.1 SDK it is possible to target version3.0 and version 4.0 .NET MF applications as well.  This means that you don't have to migrate your solutions immediately to use the new features of version 4.1 SDK

3)   Improved application diagnostics for code size, available at deployment, and memory requirements, available programatically through Microsoft.SPOT.Reflection.GetAssemblyMemoryInfo()

4) DPWS changes and new samples.  Windows 7 and WCF 4.0 full compatibility and discoverability.  Support for DPWS custom bindings.

5) Hashtable implementation for the standard typein System.Collections.  This feature was contributed by Eric Harlow through the .NET Micro Framework community acknowledging the original idea from Rob Miles and extensive support from Jan Kučera. 

6) SPI interface changes for added flexibility and perfromace

7) Support for Big Endian processors - this enables a number of processors that we could not support in the past.  The result is seen in item #11 below.

8) Port for Atmel microcontroller SAM7S256 with 256Kb ROM and 64Kb RAM - this enables some really small applications

9) Basic support for lwIP TCP/IP open source stack: TCP/IP tested, work on this will continue through the beta. The current EBSnet stack will continue to be available and I will write a separate description of how that will look.

10) Basic support for OpenSSL open source stack for SSL: certificate parsing and cryptographic support compiling and tested, work on this will continue through the beta

11) 4 ports for Renesas SH2/A processors and development boards:  SH7216_RSK, SH7264_M3A_HS64, SH7264_RSK, SH7619_EVB

Since Renesas processors are new to our lineup - here is a brief description:

<SH7264>

Including SH2A-FPU core @144MHz and on-chip large capacity RAM. It has on-chip abundant connectivity

functions such as Hi-speed USB/SD Host/CAN, and on the top of that it has on-chip peripheral functions

such as display controller suitable for industrial equipments and various communication equipments.

<SH7216>

Including SH2A-FPU core @200MHz and on-chip Flash memory.It has on-chip abundant connectivity functions

such as USB/CAN/Ether, and on top of that it has on-chip peripheral functions such as multi-function timer

units for Motor control and 12 bit A/D converters suitable for industrial equipments and various communication

equipments such as office automation and personal computers.

<SH7619>

Including SH-2 core @125MHz. It has on-chip Ethernet controller and Ethernet PHY.

It has on-chip host interface fuction suitable for connecting another microcontroller.

Go to http://connect.microsoft.com/directory/non-feedback and sign up for the .NET Micro Framework 4.1 beta by navigating to it in the listing and clicking on 'Apply Now'.  Please give us your feedback on the Connect site at the version 4.1 Beta newsgroup.