OK, well the main risk of uncontrolled GD are a large baby which can cause a problamatic vaginal birth (eg shoulder dystosia where the baby can get "stuck")]. The baby may also suffer from hypoglycemia (low blood sugar) after birth (which is where the potential for the pushing of formuala feeding comes in.)
There is also a risk of stillbirth as prolonged high glucose can prematurely age the placenta and it can simply "fail". This is the reason that many hospital protocols are to induce at around 38 weeks for some GD patients.
HOWEVER, there is no reason in the world to expect that you will suffer any of these complications if you have been promptly diagnosed and don't intend to ignore all medical advice from here on in and sit aroud eating donuts 
First line of support should be a low GI diet. Basically low carb and no refined sugars. You will have to check your blood sugars several times a day (usually first thing in the morning and 1 hour after every meal)
If you can't keep your sugars within range by diet (and many people including myself can't) then you will be offered metformin or insulin. It's easy to feel that you have failed if you get to this point, you really haven't.
You should be offered regular scans to monitor your baby's growth.
IMO your own blood sugar readings and scans should give you some indication as to how things are progressing and may need managing (eg early induction) rather than a standard hospital protocol but do be warned that it can be an uphill struggle sometimes.
Do use the support thread, it's great.
Good luck. And don't forget it's all worth it when you hold your baby in your arms. 