This processor fills a rare niche. It has nearly double the performance of CPUs like the 53 watt Intel Haswell G1820 while having a TDP of only 35 watts. You also get several other features not found in the lesser Celeron and Pentium (non-i3) processors. Most of Intel's lower power versions of CPUs are OEM-only and not available retail. This is one of the rare exceptions.
So if you want higher-end performance while saving power (and heat), the 4130T is a good choice. It's an especially ideal choice for a higher-end HTPC or other application where cooling, power consumption, and/or fan noise is an issue.
It's not clear if Intel will even offer any lower-end socketed Broadwell (5th generation) processors at all. Most of them are BGA (soldered in) versions for laptops and possibly a few high-end quad core desktop socketed versions. So waiting for something around this price in the Broadwell family might be misguided. It's buy the 4130T now or wait for the 6th gen chips which might not be socketed at all.
Intel Core i3-4130T Processor 2.9GHz 5.0GT/s 3MB LGA 1150 CPU, Retail