When you publish an InfoPath Form through Central Administration, a few things happen:

1. Central Administration creates a WSP package for this form.
2. Central Administration creates timer jobs to deploy the package to each of the web applications that uses this form (defined by Activate to Site Collection, in Central Administration)
3. Administration Service on each server then runs the timer job to deploy the form.
4. The deployment job actually does a bunch of things:
1. Creates a list of upgrade templates in \14\TEMPLATE\FEATURES\FT-01-72d7f7bc-0c6e-ba52-fa91-bb24c0014ed6
   Note, for some sites, this list is incredibly long, and can take a long time. I can't think of any good reason why we need all the versions, but may be this can potentially affect form upgrades.
2. Creates a content type for the form
3. Copy the form template to %site collection%/Form Templates/template.xsn
4. (do other stuff)

Review this article from Microsoft: http://blogs.msdn.com/b/infopath/archive/2006/10/23/behind-the-scenes-of-administrator-approved-form-templates.aspx 

So when a form is stuck on "Installing" or "Upgrading"

1. Check timer jobs. If there are jobs that can't start - they will wait
1. Check all administration service are running on both servers
2. Check timer service is running (timer service calls administration service to deploy)
2. If your administration service is OFF, then you can try using the command line to execute those timer jobs
1. stsadm -o execadmsvcjobs
2. The benefit is if there's exceptions thrown here you'd see it in the console
3. Do this on all SharePoint servers. If the administration service is running, then this stsadm command won't do anything.
3. If your job is missing, you can check in Solution Management /_admin/Solutions.aspx
1. Go to Solution Management under Central Administration /_admin/Solutions.aspx
2. Find the farm solutions that for the form. The name would be form-formname.wsp.
3. If the solution isn't deployed, you can select deploy - global
4. If your admin service isn't running, you'll get a warning saying that jobs are scheduled but no admin service means they won't run.
5. Use stsadm -o execadmsvcjobs
4. If nothing else works, or if we want to do a complete removal.
1. In form templates, select the form template, and hit Remove.

Form is stuck on "Deleting"

1. Go to Solution Management under Central Administration /_admin/Solutions.aspx
2. Find the farm solutions that for the form. The name would be form-formname.wsp.
3. If the status is Deployed, then retraction hasn't started.
4. Click the package and select Retract Solution.
5. If your admin service isn't running, you'll get a warning saying that job is scheduled but no admin service means they won't run.
6. In command line, stsadm -o execadmsvcjobs, on both servers.
   C:\ > stsadm -o execadmsvcjobs
   Executing job-application-server-admin-service.
   Executing job-password-management.
   Executing solution-deployment-form-tradepackageform.wsp-0.
   Operation completed successfully.
   
7. You'll see this back on solutions.
   

Name:    form-packageform.wsp
Type:    Core Solution
Contains Web Application Resource:    No
Contains Global Assembly:    No
Contains Code Access Security Policy:    No
Deployment Server Type:    Front-end Web server
Deployment Status:    Deployed
Deployed To:    Globally deployed.
Last Operation Result:    The solution was successfully retracted.
Last Operation Details:   
SRV02 : The solution was successfully retracted.
SRV03 : The solution was successfully retracted.
Last Operation Time:    1/8/2013 11:01 AM


8. You can then remove the solution package.
9. If you go back to Form Template management, the form will be removed from the list, and you can re-upload as usual.