Others have echoed the same sentiment. If you have one or more Squeezebox players, iPeng is reason enough to buy/own an iPod touch.
UPDATED for version 1.5
Welcome improvements, but still next to useless in landscape mode - please update the landscape UI to make the Now Playing as feature-rich as portrait. Theres no reason to have such an ugly landscape mode.
UPDATED for version 1.3.3
Not usable as a player on iPod Touch 1st and second generation - very buggy with a lot of drop-outs. As a controller it works, but its also extremely slow, especially when waking from sleep. It can take up to a minute to update the current track details. Dismissing the TIPS/HELP doesnt seem to work in iPod touch as the program constantly keeps popping up instructions.
On the iPhone 4 the program works much better and is highly recommended. However, performance is still an issue with occasional drop-outs when playing - it is not as bullet-proof as a real Squeezebox. The program will often become silent if pausing a track and using another app - come back to iPeng and you no audio will output when playing tracks.
A concern for all devices is excessive battery usage. This program is a very big battery hog, even when not actively in use. On devices with multitasking, just leaving iPeng running and not playing any music will cause the device to drain to zero battery in the course of an afternoon. This happens on the iPhone 4 as well as various iPod touches Ive tested.
UPDATED for version 1.3
The update seems to start up very slowly, sitting on a black/blank screen after the title screen for quite some time.
It kind of stings to have paid for Squeezecast (another app) twice - with Playback supported here Squeezecast can be tossed.
The landscape view still needs work as currently there are no transport controls in that view, making it impossible to switch tracks. Id also love to be able to see more details about the music being played as well as be able to instantly bring up additional tracks by the same performer with no more than a couple of clicks.
Please consider moving the button for the in-app purchase onto the visible screen - currently it is hidden out of view and it doesnt look like the page can be scrolled. Put it right near the top of the playback info and put the FAQ items down below. That will get you less frustrating in-app sales.
Also, you must quit iPeng and restart (force quit from the multitasking bar) in order for in-app playback to work!
Previous Review:
Its quicker and more convenient than a Web UI to control your player, plus its infinitely better than Logitechs own Controller. IMO, Logitech has really missed the boat by not supplying their own controller application, but their loss is iPengs gain.
There are still some small issues and tweaks that need to be addressed, but the vast majority of customers will never notice the items Im referring to, so I wont even mention them here.
Heres my best praise for this app: Apple should take note and rework their iPod app to be more like iPeng in some respects.