CONSOLIDATED BALANCE SHEETS (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Current Assets:
Cash and cash equivalents	$ 17,392	$ 12,526
Short-term investments	55,301	49,048
Accounts receivable	54
Due from related parties	321	828
Unbilled receivables	402	8
Prepaid expenses and other current assets	461	846
Total current assets	73,931	63,256
Restricted cash	622	622
Property and equipment, net	2,260	2,776
Long-term investments	14,521
Other assets	73	117
Total assets	91,407	66,771
Current Liabilities:
Accounts payable	528	239
Accrued expenses	3,613	4,085
Current portion of deferred rent	165	165
Short-term deferred revenue	2,651	1,906
Total current liabilities	6,957	6,395
Deferred rent	262	386
Long-term deferred revenue	36,200	36,207
Other long-term liabilities	116	107
Total liabilities	43,537	43,095
Commitments and contingencies (Note 11)
Stockholders' Equity:
Preferred stock ($0.01 par value per share); 5,000,000 shares authorized; no shares issued or outstanding
Common stock ($0.01 par value per share); 100,000,000 shares authorized at September 30, 2011 and December 31, 2010, 34,088,286 and 26,895,389 shares issued and outstanding at September 30, 2011 and December 31, 2010, respectively	341	269
Additional paid-in capital	283,620	230,299
Accumulated other comprehensive loss	(32)	(15)
Accumulated deficit	(236,059)	(206,877)
Total stockholders' equity	47,870	23,676
Total liabilities and stockholders' equity	$ 91,407	$ 66,771