Stockholders' Equity (Tables)

6 Months Ended

Jun. 30, 2012

Stockholders' Equity [Abstract]

Weighted average for key assumptions used in determining the fair value of options granted

The weighted average for key assumptions used in determining the fair value of options granted during the six months ended June 30, 2012 follows:

Expected price volatility	82.71%-82.97%
Risk-free interest rate	0.76%-1.02%
Weighted average expected life in years	6 years
Dividend yield	—

Summary of stock option activity

Option activity during the six months ended June 30, 2012 was as follows:

	Number of Shares			Weighted Average Exercise Price Per Share		Aggregate Intrinsic Value
Outstanding at January 1, 2012		4,553,251		$	3.66
Granted in 2012:
Officers and Directors		223,674			1.85
Others		360,540			2.14
Exercised		(179,178	)		2.29
Forfeitures		(250,741	)		3.26
Outstanding at June 30, 2012		4,707,546		$	3.50	$	6,171,895

Summary of stock options outstanding

Options outstanding at June 30, 2012 are as follows:

Range of Exercise Prices	Number Outstanding		Weighted Average Remaining Contractual Life (Years)		Weighted Average Exercise Price		Aggregate Intrinsic Value
$ 1.00 – 5.00		3,796,301		6.28	$	2.87
$ 5.01 – 10.00		911,245		5.17	$	6.30
		4,707,546					$	6,171,895

Summary of stock options exercisable

Options exercisable at June 30, 2012 are as follows:

Range of Exercise Prices	Number Exercisable		Weighted Average Remaining Contractual Life (Years)		Weighted Average Exercise Price		Aggregate Intrinsic Value
$ 1.00 – 5.00		2,979,443		5.56	$	2.95
$ 5.01 – 10.00		911,245		5.17	$	6.30
		3,890,688					$	4,619,278

Summary of non-vested stock options

A summary of the status of the Company’s non-vested stock options as of January 1, 2012, and changes during the six months ended June 30, 2012 is summarized as follows:

Nonvested Shares	Shares			Weighted Average Grant Date Fair Value		Aggregate Intrinsic Value
Nonvested at January 1, 2012		786,188
Granted		390,206
Vested		(289,952	)
Forfeited		(69,584	)
Nonvested at June 30, 2012		816,858		$	2.72	$	1,552,617

Summary of warrants outstanding to purchase Common Stock

Warrants outstanding at June 30, 2012, all of which are exercisable are as follows:

Range of Exercise Prices	Number Outstanding		Weighted Average Remaining Contractual Life (Years)		Weighted Average Exercise Price		Aggregate Intrinsic Value
$ 0.01 – 5.00		2,291,301		2.45	$	3.80	$	1,987,505