Did you do what I asked earlier?  Put just the airline selection between quotes to see if you have white space issues or maybe case sensitivity problems.

I'm not sure what else I can do for you, this works fine for me, and I even augmented my page and controller to use a selectList like yours.  If you try my example in your own org, you'll see that when you make new selections from the drop downs the index will disappear/reappear accordingly and the right hand column will update.

<apex:page controller="airlineCon"> <apex:form> <apex:pageBlock id="theTable"> <apex:pageBlockTable value="{!records}" var="t"> <apex:column> <apex:actionRegion> <apex:selectList value="{!t.airlineSelection}" size="1" required="true"> <apex:selectOptions value="{!options}"/> <apex:actionSupport event="onchange" rerender="theTable"/> </apex:selectList> </apex:actionRegion> </apex:column> <apex:column > <apex:outputText value="{!t.i}" rendered="{!t.airlineSelection != 'Jet Blue'}"/> </apex:column> <apex:column > <apex:outputText value="{!t.airlineSelection}"/> </apex:column> </apex:pageBlockTable> </apex:pageBlock> </apex:form> </apex:page>

public class airlineCon { public List<record> records {get; set;} public airlineCon() { records = new List<record>(); for (integer i = 0; i < 5; i++) { records.add(new record(i, 'Jet Blue')); } for (integer i = 5; i < 10; i++) { records.add(new record(i, 'United')); } for (integer i = 10; i < 15; i++) { records.add(new record(i, 'US Airways')); } for (integer i = 15; i < 20; i++) { records.add(new record(i, 'Delta')); } options = new List<SelectOption>(); options.add(new SelectOption('Jet Blue', 'Jet Blue')); options.add(new SelectOption('United', 'United')); options.add(new SelectOption('US Airways', 'US Airways')); options.add(new SelectOption('Delta', 'Delta')); } public List<SelectOption> options { get; set; } public class record { public String airlineSelection { get; set; } public Integer i { get; set; } public record(Integer i, String airlineSelection) { this.i = i; this.airlineSelection = airlineSelection; } } }

The answer to the original question is that {!t.airlineSelection != 'Jet Blue'} is the proper syntax.  If that's not working for you then you have other problems on your page.  Possibly airlineSelection is not exactly 'Jet Blue', or possibly that expression has nothing to do with your problem at all, and you've got something else going on.

You really need to make sure you know exactly what the value is, which is what I suggested in my second reply. Similarly you can put {!NOW()} next to the inputField with the rendered attribute to make sure that that column is getting rerendered (it will put a timestamp on your page and if your column is getting rerendered, you'll see the timestamp update).

Hope this helps.