Wow Dejavu!
I was also deciding between the iMac and the mini. In fact, I actually bought a Dell 20" widescreen monitor which I loved, but after the iMac update I jumped on that bandwagon.
Both machines seem to run the basic stuff at almost the same speed. I tested both at the Apple store in Cleveland and honestly couldn't tell a difference in speed with basic things like Firefox, Word, Photoshop, etc. If you plan on playing games or any type of intensive editing, it seems the iMac will be your best bet of the two. Also consider how long you want to keep your machine. An iMac should outlast a mini because of it's superior technology.
When thinking about which computer to get, think about what you do now, but also think about what you might want to do within say 2-3 years. Any movie creation, etc.
Although looks shouldn't necessarily be a major factor, remember you will be staring at the machine you choose for some time.
I would suggest looking into the Dell FPW2005. It is truly a brilliant display for cheap -- around $500.
One last thing -- are you a student? Apple is currently running a promo which entitles students to receive an extra $100 off the iMac in addition to the original EDU discount. Might be something to consider, again if you are a student.
Hope that helps somewhat.
