What version to go for (updgrade) after SQL Server 2000???

I have developed one project very long back in .NET Framework 2.0 and SQL Server 2000 for one doctor in USA. He is still using that software but since than many rules gets changed in USA so he come back to me with those changes and also told me that I want to use latest technology for my project and database.
He might have searched internet for getting knowledge about the latest version of .NET and SQL Server. Talking about SQL Server, he told me that the latest version of SQL Server is “Denali” and I want to use it in my project. While talking about this, I made him understand that we should go for SQL Server 2008 R2 rather than “Denali” by giving some very strong and valid reason and one of that strong reason is “Denali” is not in production, it is in CTP (Community Technology Preview).
But after this discussion, I felt to share some of my personal opinions on this blog.
After SQL Server 2000 version, you have three choices for upgrade.
1.)    SQL Server 2005
2.)    SQL Server 2008
3.)    SQL Server 2008 R2
I am excluding “SQL Server Denali” from this as it is still CTP version, not good to choose it for production as of now though it has eye catchy and flashy features which attract you.
Out of these three versions, I would, personally, like to go for “SQL Server 2008 R2”. Let me tell you why I am thinking this.
SQL Server 2005 is not a good deal at this time, though it has upgraded engine and many new features as compared with SQL Server 2000, SQL Server 2005 is now in “Extended Support”. It means you will neither get any “No-Charge” support nor claim any warranty. Soon after release of “Denali”, Microsoft may end even “Extended Support” for SQL Server 2005 (may be in 2014/2015).
While compare SQL Server 2008 with SQL Server 2008 R2, R2 gives much more facility than SQL Server 2008, mainly multiserver management, greater security, self service BI and many more.
Apart from that, SQL Server 2008 was released in 2008 and SQL Server 2008 R2 is released in 2010 so you will get longer support in “SQL Server 2008 R2” then “SQL Server 2008”, means better reward of your money. 
Generally in any SQL Server, you get support for your version for minimum 10 years. Suppose SQL Server 2008 R2 releases in 2010, Microsoft will definitely give you support for SQL Server 2008 R2 till 2020. For detailed understanding of support life cycle, refer Microsoft website from here. You have to go to “SUPPORT LIFECYCLE” tab in that link.
This is what I am thinking; this article is totally based on my personal view. You have to decide the proper version by looking at your need; this article is just the guideline to make you aware with some of the facts which may help you in your decision.
Reference: Ritesh Shah

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