I've been running Vista and Seven without a page file for a long time, without any issues. Recently, I had a need to activate the page file, and did so reluctantly, with the goal being that disable it when the program is no longer used.
Just for the kick of it, I've tested the page file usage with process monitor. For a little over an hour I used the system regularly that included Web Premium CS5, Outlook, Excel, Word, Black Ops, etc. The memory utilization was around 70% at its peak, or about 6GBs. This is what process monitor recorded for the page file during this time:
File Time Total Events Opens Reads Writes Read Bytes Write Bytes Path
16.37376 3,600 4 16 3,580 258,048 3,753,902,080 D:\pagefile.sys
That's a lot of writes to the page file within the timeframe that the activity had been monitored. It wasn't only the system in itself, all other applications at the time of their start and even afterward did write to the page file as well. The 3.75GB total writes is a big chunk, especially when the page file is set to size 4GB. During a full day or so the this write bytes could easily would be in the 20-30GB range; it may require extending the page file size, or let the system overwrite existing entries.
The same system had no issues running without the page file and maybe it's just a subjective observation, or placebo affect, but the system didn't feel as snappy as without the page file.
Based on what I've seen and how the system felt during this time, it seems like a better option just to disable the page file and let Windows deal with the available physical memory only.