First off I should mention I adore Xbox Live and always have. It is the core Xbox feature that for me and many others, thrusts the platform far beyond that of what Sony and Nintendo currently offer. The fascination of sharing team instructions, having a laugh and of course belittling the enemy proves too wonderful to resist when it all works.
Ever since the Microsoft Xbox 360 console appeared, Xbox Live has quite rightly evolved with some truly remarkable features that expanded the system far beyond the original Xbox. There was an oversight though that aggravated many users and this was the lack of a dashboard chat option.