..where a (good) programmer spends most of his time: in the documentation!

Compare:

http://java.sun.com/j2se/1.5.0/docs/api/java/math/BigDecimal.html
http://msdn2.microsoft.com/en-us/library/system.decimal.aspx

.NET: DHTML-y, corporate-y, Outlook-y. Looks like the sort of webpage that would have "document.all", though fortunately not.

Java: Looks like a page designed ten years ago, because that's more or less what it is.

Neither is valid (X)HTML.

Comparing the content, Java is definitely the geeker of the two. See:

Appeals to ANSI or ISO standards to explain behavior:

Java: 5 uses of the word "ANSI"
.NET: none


Sample code that is US-dollar centric, without reminding the clueless reader that it might be a bad idea to copy this code into a Foreign-Exchange application:

Java: no
.NET: yes, in all known .NET languages

Number of ways to "round" a number:
Java: 7 (number of values of the RoundingMode enumeration)
.NET: 6 (count of overloads of "round" method on System.Decimal, including both possible MidpointRounding values)

Use of something that looks like BNF:
Java: yes
.NET: no

Use of numeric Unicode references ("\u002B"):
Java: yes
.NET: no

Other terms appearing only in Java docs:

scale
semantics
addend
augend
minuend
subtrahend
multiplicand