the solution to solve this for me was incredibly simple, i was lagging during sms keyboard entries, and contacts scrolling, and other genreal animation lags, simply going into mail settings and turning off contact syncing solved this problem entirely, i just let itunes sync the contacts up, whilst this is technically subtracting a feature of the phone, 'over the air sync' its a temporary and good solution until apple fixes this obvious flaw. let me know if it fixes your lag!