Just going to throw in my two gold here. I'm a level 34 Wizard / Bard, and so far everything has been pretty good, and the few skills I've taken have proven their merit in particular situations.
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Moving March - An obvious pick from the Bard skills. I mean really, who doesn't like making the whole party move faster?
Mana Cycle - I love it. I do use MP potions once in a while, but I no longer bother to have it on auto. When I see I'm running a little low, I switch to my harp to cycle, and switch back in a flash so I can keep pumping out damage.
As an aside to this, switching does get rid of Life Control but when I'm in a party, I tend to save that for party giants so its not a huge concern to me.
When I am solo, I keep Life Control on, and have my auto pots for health set to 49%. Why? Let's face it, monsters are either going to one shot me, or two shot me. If they two shot me, my health is going to dip below the 49% line for the pots to kick in anyway. With this in mind, switching to a harp does not cause me to needlessly use up hp potions when I need to Mana Cycle. I simply reapply myself and keep going.
Temptation - An interesting form of crowd control that you have to be quick with, and use with a little trial and error. I primarily use this to either:
a.) Quick confuse a mob so it backs away from other squishy party members, or myself.
b.) Get laughs out of watching free cock fights outside of town.
One thing I like about this skill, is even if there are no other enemies around the monster you hit with Temptation will no longer be aggressive for the duration of the Confusion. Sometimes they might even go off looking for something to beat up.
Another note on its usefulness in protecting party members, is in instances where two monsters are chasing someone in circles, confusing one will cause it to attack the other and they'll both start fighting each other, ignoring your friend completely.
It's also good if for example, you're fighting a party mob with your pet like I do sometimes, and you need a little help. When fighting party chickens solo (am I crazy or what), if there is another chicken nearby, I will confuse it, and more than likely it will come over and start helping me kill the party chicken.
Noise - Easily my favorite of the bard skills. Although there may be periods where its not as helpful as you approach the level where it gets upgraded, this skill as someone mentioned earlier stops general aggressive monsters from attacking you at random. Helpful when solo and in parties for that random monster that just happens to spawn on your backside and you don't have time to react.
Discord Wave - One I have asked about, but have finally been able to use for myself. This skill targets party members (or yourself) and emits sound in a small radius around the player, and any monsters in range will have their aggression towards you reduced. Be warned though, this skill will not cause aggressive monsters to stop attacking completely, but can have its advantages, and I can give two examples of where you may use it.
1.) I was in a small party that unfortunately had no warrior to keep the monsters attention, and the monster would constantly turn towards a cleric or wizard. Since I had my wolf attacking the party mob also, I would use Discord Wave on my party members, and divert its attention to the wolf. So in a nutshell, if you have a trigger happy party member, or you happen to be trigger happy, this skill will divert the monsters attention to someone else.
2.) Solo again, I've found a somewhat slow but sure way to kill general party monsters (haven't tried party champions) and Giants, but you'll need a pet to keep attention. So, you first let your pet attack the monster to draw its attention, then you can proceed to start taking a few shots with your staff. After maybe 3 shots the monster will turn to you, so you can quickly switch to your harp and hit discord wave causing the monster to turn back onto the wolf.
Use Discord Wave on yourself one more time and you should be setup to start. All you have to do is switch between Discord Wave and one of your Nukes till the party monster goes down, and be mindful of your pets health. So it's basically like this.
Pet Attacks -> Staff hits -> 2x Discords -> Nuke -> Discord -> Nuke -> etc.
When going back and forth between nuking and Discord Wave, I was not hit once. And with that, Discord Wave earned a cozy little spot in my hotkey bar.
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Well that was certainly alot more than 2 gold, but I won't tell

Hope I helped anybody out who was thinking of using Bard.