According to Vincent aka @veeence, who has very good contacts with The iPhone Dev Team, informed that an unlock for iPhone 4 with baseband 2.10, 3.10 & 4.10 will be released in 2 weeks after the release of iOS 4.3 (Final Version). Veeence is confirming that unlock for iPhone 4 will not be released immediatley after the iOS 4.3 releases, it will take atmost 2 weeks. Most likely to exploit the latest baseband 04.11.02.
iOS 4.3 is expected to Release on 13th or 14th February. So we can expect Ultrasn0w Unlock for iPhone 4 Baseband 2.10.04, 3.10 and 4.10 at the end of February. Stay Tuned we will update more on this news!