My take on the current logos:
Cairns - Good logo, don't change. Maybe a tad too graphical or cartoon like, but its lasted since 1999 and its not looking dated yet, though it will eventually.
Perth - Nice logo, clean and contemporary design. Been around since the early 2000's and no sign of ageing just yet. Maybe due for a slight tweak in the next few seasons, but nothing radical. Don't change, and I don't think they will anyway.
New Zealand - Way too simple, needs a bit more into it other than a ball and a swirl. However, it works well into their jersey's. Not sure about changing it though.
Melbourne - Terrible, clip art like tiger, and average font used. Nothing like their past logos, so a major backward step. They have nice uniforms though, and their logo doesn't look so bad there, but thats the only place it looks OK. No point changing so soon after launching it unfortunately.
Adelaide - Very average, similar to Melbourne's, but not as bad, and I don't like their font. Their previous logo was miles better. Did not need a new logo at this stage.
Wollongong - Its OK. The Hawks font looks a bit heavy for my liking. No need to change for a few years though, as its still quite new.
Sydney - Terrific logo since they have used it since their inception (1988) with only minor tweaks. I don't think they plan on changing it anytime soon, nor should they.
Townsville - Poor logo in my opinion. The Croc is too cartoon like, they have the McDonald's golden arch sponsor incorporated too heavily, and the Crocodiles font is too decorative or "cartoony". Its more of a miss than a hit. Definitely due for something new. Perhaps will change to say "Brisbane Bullets" next season? ;) - I hope not of course...