Apple has finally released the final version of  users. 

After three releases of Beta versions of iTunes 10.5.1, Apple has finally released the final version of iTunes 10.5.1 and iTunes Match, after a testing it by releasing three beta versions to Developers, to grant a smoother and good experience to iPhone, iPod Touch and iPad users. However, it isn't available for everyone. It is currently available in United States only. If you fall under this category, you can 
Apple stated about iTunes Match:

Here’s the music iTunes matches plays back from iCloud at 256-Kbps AAC DRM-free quality — even if your original copy was of lower quality.

With iTunes Match, you will be able to store your tracks in the iCloud and access them from every device running iOS 5 whether it is an iPhone, iPod Touch or iPad. This iTunes Match service costs only $24.99 per anum. You can store up to 25,000 songs and run them on ten devices and the songs you purchase from iTunes won't count in this list. You will have to set up and sign up for iCloud and after you  Match" Option under the left side bar.

Well, if you want to download the iTunes 10.5.1, just  below and enjoy.

• Download iTunes 10.5.1 Final With iTunes Match (Apple.com)