Apple laptop

I don't recommend boot camp because it you have to shut down one OS to run the other. Instead, consider a Virtual Machine like VMware or Parallels to run the Win OS of your choice. Then, as Roylong suggests, test. Purchase MS Office 2011 with Outlook to get the Exchange connection.
Check out SQL for Mac. The is a an extremely robust version of Unix after all.

As for Sharepoints, sometimes tricky, sometimes easy.

The trick is to get as much working as possible on the Mac side but have the VM just in case or until you are satisfied with the Mac side of things.

To answer your question about Office communication client - there is a Communicator for Mac  - see http://www.microsoft.com/mac/enterprise/communicator
The full office suite is also available.

Sharepoint will work ok, but unless you use Internet Explorer for Mac or open files directly from office applications, you will have to download files to your desktop to check them out.  See https://docs.rice.edu/confluence/display/ITTUT/Sharepoint+on+a+Mac+OS

If you want to run Windows applications on a Mac, purchasing Crossover is the best option as you don't need to resort to either dual booting or running a virtual machine, both of which aren't really useful for day to day operation.  

Why do you particularly want an Apple Laptop?  is it for cosmetic reasons or because you like the Mac OS, or because someone told you they are better?  If you want it to run primarily Windows applications, then Windows will definately be better.  I have a machine running Mac OS and I find it much more difficult to get it to do anything non-Apple related!

- other experts have share their view on other products. i would answer on Oracle:

: i've never installed one on Mac OS. however i'm using MacBook Pro running Mac OS and Windows 7 on bootcamp. My Oracle database in on Windows.
: i agree with both expert recommendation, you can either use bootcamp or VM to run Windows and installed Oracle on Windows.

: if you want to stick only to Mac OS, yes Oracle database in available for Mac OS X on Intel therefore no need to run it on a VM:
Oracle Database 10g Release 2 (10.2.0.4.0)  for MAC OS X on Intel x86-64
http://www.oracle.com/technetwork/topics/macos/whatsnew/index.html
http://www.oracle.com/technetwork/database/10204macsoft-x86-64-092720.html

OP

I suggest the user is asking about oracle user applications not Oracle databases.

I disagree with respect to Crossovers. It is a bit of a kludge and supports only a very narrow range of Windows applications. VMWare Fusion and Parallels work virtually seamlessly as long as you have enough RAM and a big hard drive.

If you are going to get a MacBook Pro, splurge for 8 GB of RAM and the 500 GB solid state drive if the budget will stretch that far and it will FLY !

Agree about crossover; never did work properly - even on the stuff that was apparently supported.

Internet Explorer for Mac?  We are now in 2011 and IE for Mac has not been around since.. ...since.. since... I can't remember, that's how long :/

Agree that virtualisation could be an option.. ..also agree that the only way to get really good performance with both VMware and Parallels is with loads of RAM and an SSD hard drive.. ..expensive option; although potentially worth it - which is why I recommended Bootcamp in the first instance.

Really does depend how the questioner wants to use their computer..

"I suggest the user is asking about oracle user applications not Oracle databases."
- until he confirm on this, i stand corrected on database explanation.
- if you care to read, in the link provided in ID35957642 listed oracle client and oracle sql developer tool supported on Mac OS for connecting to Oracle database server on the same machine or located on the server/other machine.

hi,
let me try with bootcamp and so that I can choose OS when mac book starts
thanks a lot for everyone