Most builds are viable, if they are played intelligently and with good knowledge of the server.
However, there have been certain changed to bards, such as:
"Bards with less than 30 base Cha receive 5% less than the listed concealment below." (Spell Changes Documents, Bard, Ethereal Visage)
the Legendary Artist feat, which grants another song level on top of the Artist feat
Bard epic duration is based on Charisma. "(...) it is available for one round per day per point of base Cha possessed by the bard. Points above 30 are halved for this calculation." (Custom Epic Spells document)
There are also a number of almost required bard epics, like Transmutation (UUU), Enchantment (HMR), Illusion (Possums) and Necromancy (DotD). Of those only the Necromancy epic is not a must-have epic, in a strict way. With a base charisma of 16 at double demi this build also has a real problem with epics.
Balduvard's build also makes use of the Rapier Wit feat, which allows you to use your Charisma modifier for AB when using a rapier. This makes it possible to have a melee bard with high AB, decent damage (thanks to Divine Might) and about 40 rounds of bard epics.