Well, I'm just a first year Engineer but in my program design class we were taught that if you need an infinite loop you should rethink your program design because every non-realtime program should terminate _eventually_.

Given then, that you still need an infinite loop, I have to ask if you will be collaborating with others on any script where you might use this. If you're just writing scripts to run on your basement webserver, it's not a problem at all but if you plan to work with others, readability, in my opinion, becomes one of the most important factors.

In the end, I suppose, it just comes down to what you (and anyone you work with) require out of the script - if it's performance, to hell with readability; if it's future tweaking, make it readable instead of fast, etc.