I would unless you want it to bloom so you can save seeds (if its an unusual variety). It's bitter to eat so use the space for something else.

Dave

Personally I would uproot it and remove it from the garden area. Bolted lettuce would likely be bitter tasting, the bugs will infest the rest of your garden etc.
Replace the lettuce with another crop.

Thanks for the advice. I went ahead and uprooted all of the budding lettuce. I'm actually not quite sure which variety of lettuce it was either but it did yield a fair amount earlier on, which I harvested.

Actually, I found a chart I drew up and it looks like I planted mesculin in the box that bolted like crazy. Checking it out, looks like it's the mustard tendergreens that were the culprit.

Just thought you might like to look over text and photos all about growing lettuce. It's a great presentation and very informative. From the link below, click on "Techniques" then on "Lettuce". EVerything there is based on the organic methods of the great horticulturist, Alan Chadwick. If you follow the techniques closely, you'll have much less bolting to deal with. One of the most important things to remember is that when you transplant seedlings into the final beds, never get water on their leaves for three days or so. Just water around the roots after planting out, and that should hold them until you can water overhead later. The reason is that water on leaves stimulates leaf growth, but what you want is for the plants to get their roots well established first.

Here is a link that might be useful: Alan Chadwick