MACUPDATED  Excellent FTP client, it's one window interface is very easy to use. Also, by far the fastest client I've used (previously used Cyberduck), the 10 simultaneous transfers makes so much difference. Not the prettiest looking, but it makes up for that with it's ease of use and features.  
(Version 3.2.1rc1)

MSWFUJOWDFFYC  Poor FileZiila.... They do release candidates for weeks, and then when 3.1 finally comes out, they have to do a bug-fix for it a few days later. Bummer. Anyway... This is not a bad FTP client, especially for free. It's probably more for the bit-twiddler geeky types though. I applaud them for continuing to aggressively develop for the Mac. THANK YOU!  
(Version 3.1.0.1)

TIM27  This program is awful compared to both Cyberduck and Rbrowser. It disconnects after about a minute and you have to reconnect all the time. Adding new hosts is unintuitive. Interface is terrible. AND it doesn't allow you to drag files from the desktop to upload/download. You have to drag them from one window pane to the other.

Overall = bad program. Good thing it's free.  
(Version 3.1b2)

SOUTHPAWAMI  The 'stable' version is the version you want to download. It works fine, very quick to connect. I have a license to YummyFTP 1.7.2, and use it. I may use the stable version of this depending on how effective it is with file transfers over time.

Yes, it's ugly. It needs a two button mouse. This is true. Most of the multi-platform software that works on Linux, Windows, and OS X don't appear very nice from an image and one-button mouse perspective. The main question is whether it functions. Yes. You simply put your ftp server, user name, and password in the upper box. It remembers it if it connects fully. After that, it will remember until you tell it to forget. Oddly... the option to forget is in the same menu as all your quick bookmarks... making the whole accidents happen a concern.

Permissions is very GUI friendly as well. All 9 options are available via point and click.

The interface takes a minute to get. The empty screen near the top is the log screen. The two screens on the left below that are the files on your computer. In the top one, you pick a directory, and the window below that shows you the contents of that directory. It only seems weird at first... some seconds later your thinking this is fast... and it's the layout that contributes to the impression.

The empty two windows on the right are the remote directories from the host.

It'll take time for me to determine if the file transfer is as reliable as Yummy. It does log into my domain faster, displays the contents of directories faster, and shows a file viewing in a timely fashion.  
(Version 3.3.0-beta2)

ANONYMOUS  i think this app really needs improvements. not just the mac version, but for windows as well. i use cyberduck and its much better. it is free as well, and when releasing new versions its got new featurs, not just bug fixes. their interface is much better and the whole app is faster. skip this, get cyberduck.  
(Version 3.2.6.1)

TDSTOUT  I've used many clients over the years. I was very happy with Cyberduck for a long time. It looks good and worked great. Lately it developed a problem and would not work right. I reinstalled new copies and still did not solve the problem in not allowing me to move freely within the accessed ftp. So I tried FileZilla and the app works great and is very fast.

For now, I am very satisfied. Yes the interface is not pretty, like typical PC ftp apps, but it works great and is fast. What else do you really need?  
(Version 3.2.6.1)

MACFOOL  For those newbies unable to cope with minor complexities and those obsessed with style over function, this fast and sturdy app is not for you.

Otherwise is performs perfectly and it's free.  
(Version 3.2.6)

TIM27  I should restate that it disconnects not because of problems with connections to servers. Those are solid. It disconnects because the program is coded to disconnect after a certain amount of time. It's very annoying.  
(Version 3.1b2)

ST00P!D M0NK3Y  Um... it works fine... but it looks like the developers vomited a Windows interface onto the screen. Yes, it's horribly ugly, but it works just dandy. I've used this for quite a while on Windows and no problems. I still prefer Cyberduck on the Mac, though... not because it's pretty, but because it's simple and easy to use and manage.  
(Version 3.2.8)

PEDRO FARDILHA  Heh, looking at the reviews below people either love it's speed or hate it's looks!

So, basically what we are all looking for is something with Cyberduck's interface and FileZilla's multiple (and simultaneous) downloads.

Of course it would also need to me "smart", meaning that when you would transfer a single folder onto it, it would break it's contents in multiple downloads.

(I apologize for this "non-review" but I really find it curious how well segmented are the opinions here)  
(Version 3.2.6rc1)