If you want a good reference for learning .net 4.0, I can recommend this book:
C# 4.0 Unleashed by Bart De Smet
some alternatives:
Pro C# 2010 And The .NET 4.0 Platform 5th Edition By Andrew Troelsen
Programming C# 4.0 By Ian Griffiths, Matthew Adams, Jesse Liberty
Professional C# 4.0 and .NET 4 (Wrox Programmer to Programmer) By Christian Nagel, Bill Evjen, Jay Glynn, Karli Watson, Morgan Skinner
As far as certification goes, you can find the certification path on the
Microsoft Learning web site. Here you have an overview of all the possible tracks you can take concerning .net 4.0. First you need to do an MCTS-track (Microsoft Certified Technology Specialist) and after this you can go a step further by also doing an
MCPD-track (Microsoft Certified Professional Developer).
So, for the first step (MCTS), you have 5 posibilities (each link to the exam for the certification holds an overview of what the exam covers):
MCTS: .NET Framework 4, Windows Applications (exam
70-511)
- book that covers the exam:
MCTS Self-Paced Training Kit (Exam 70-511): Windows Application Development with Microsoft .NET Framework 4 Book/CD Package By Matthew A. Stoecker
MCTS: .NET Framework 4, Web Applications (exam
70-515)
- book that covers the exam:
MCTS Self-Paced Training Kit (Exam 70-515): Web Applications Development with Microsoft .NET Framework 4 Book/CD Package (Mcts 70-515 Exam Exam Prep) By Tony Northrup, Mike Snell
MCTS: .NET Framework 4, Service Communication Applications (exam
70-513)
- no books available yet
MCTS: .NET Framework 4, Data Access (exam
70-516)
- book that covers the exam:
MCTS Self-Paced Training Kit (Exam 70-516): Accessing Data with Microsoft .NET Framework 4 Book/CD Package
By Glenn Johnson
MCTS: Silverlight 4, Development (exam
70-506)
- no books available yet
Dimitri C. - Please mark the replies as answers if they help! Thanks.