Thunderbird client handles POP and IMAP email extremely well, but its search function is sluggish and presents results in a rather unfriendly mass that can't easily be selected and moved or deleted. It also requires further manual configuration to support calendaring (via the Lightning plug-in) or Microsoft Exchange.
Exchange support comes via the Davmal exchange gateway that connects to Exchange Email, Calendar and Dictionary services, plus the manual installation of Oracle's latest Java Development Kit. The set-up process isn't too involved though, and there are a number of helpful guides to help.
Running Windows Software
Linux may be a mature operating system with a fully comprehensive selection of software for just about any purpose, but there will inevitably be times when only something that only runs under Windows will do.
Oracle's VirtualBox is a very good open source VM application that should handle most needs, but it does still require the appropriate Windows licence. There will inevitably be times when only software that only runs under Windows will do.Wine, on the other hand, is a self-contained open source Windows emulator that doesn't require a guest operating system to be installed and while its support for 64-bit client applications is currently very limited, it can still run on 64-bit Linux platforms and 32-bit versions of most Windows software are still widely available.
Wine is most popular as a way to run Windows games under Linux (which says something about its performance, if nothing else), but a wide range of business-orientated applications have been confirmed as fully compatible with Wine. These include Adobe Photoshop CS3, Cisco IP Communicator and numerous specialist programs used by the accountancy and legal professions.
The Future
Ubuntu's version numbers indicate the date of release rather than an incremental numbering system so 11.10 was released in October 2011 but the animal-based code names have so far been ordered alphabetically (Oneiric Ocelot follows Natty Narwhal).
Releases are generally made twice a year and have so far been split into two types normal and long-term support (LTS). Normal releases like 11.10 are supported for 18 months with updates, while LTS desktop releases last for three years, but Ubuntu is switching for a standard five-year support cycle with version 12.04 (assuming an April 2012 release date).
Ubuntu 12.04 Precise Pangolin' refines many of the best features found in v11.10, but is intended to bring greater integration with the Ubuntu One cloud service. So far, v12.04 looks likely to still resemble 11.10, but with all the benefits and business stability that an LTS release will bring.
