This makes no sense. What happens if:
1. I am looking for a reference regarding Exchange 2010 RTM. Do I still need to put "141" or will "140" also work?
2. I am looking for an Exchange 2010 SP2-specific feature. Do I still use "141"? What about the new SP3? Do I put in "143" or do I still use "141"?
3. There are various Rollup/CU releases? For example, Exchange 2010 SP2, Rollup4v3. Do I put "141" in the url, or do I put "142.43"?
4. The first SP for Exchange 2013 comes out. Do we then change the url to go to "151"?
Etc.
This is so incredibly crazy. Geeks, not common sense designed this numbering scheme. Can't we just refer to things the way normal people would. Please make the url for Exchange 2010 = "EXCHG.2010" and Exchange 2013 = "EXCHG.2013"