He comes across as very whiny. The tactics he mentions seem pretty valid to me (and if he's mad, they must be working to some degree).<p>He should be happy Twitter haven't decided to roll those features into the platform (yet) and put him out of business altogether.
I generally agree. Ads targeting competition are fine, depending on the copy.<p>The only thing that has calmed me in similar situations is knowing that competition that does things without class doesn't do well. If your marketing is around a very small competitor instead of the usual alternative (nothing), then you're incompetent. If your product design is based on copying the competition, then you're incompetent.
All's fair in love and war, and there's no point getting bent out of shape about it.<p>That said, spending time & money on these sorts of tactics is almost always less efficient than spending time & money improving your product. Every hour you spend improving Proxlet while your competitor's fussing with AdWords and downvoting on Quora is an hour you're winning.